What is an OTP Message? Everything You Ever Need to Know About OTP, in One Place

OTP has become essential in preventing fraud and keeping your customers’ and business data safe.

Want to know more about OTP and what it can do for your business? 

In this guide, you’ll learn what OTP means and how it works so that you can implement it in your business.

Let’s begin. 

What is OTP?

OTP stands for one-time password. It is sometimes called a one-time authentication code, one-time pin, or one-time code. Whatever it is called, it means the same thing.

It looks like this

source: cm.com

It’s a temporary code that provides an extra layer of security when accessing a system or service. They are used alongside a username and password to create what is known as two-factor authentication. 

When an OTP is required to login into an account or complete a transaction, you must enter the OTP to gain access besides inputting your login credentials. 

Check out the top OTP service providers to send fast and secure OTPs. See the top bulk SMS service providers to send transactional and promotional SMS.

What is OTP authentication?

OTP authentication (also called OTP verification) is a form of 2FA (two-factor authentication) that uses OTP codes to verify a user. It is a method that a website or app uses to verify your identity when you are trying to gain access. 

2FA requires you to provide two authentication factors to access an account.

One of these factors is “something you know” (such as a password or PIN), while the other is “something you have”. This can be your smartphone or a security token, or OTP.

In the case of OTP authentication, the “something you have” is a device that receives the OTP and provides it back to the system as proof of authentication. 

How are OTPs sent?

There are several methods for delivering OTPs, each with its own advantages and disadvantages.

1. SMS (text message)

This is the most common method.

When a user tries to log in or perform a sensitive action, they get a 4–6 digit code sent straight to their phone via SMS or voice message.

It’s simple and fast, but not bulletproof, because SIM swaps and message delays are still possible. Yet, for most users, it works.

2. Email

Some platforms prefer to send OTPs to the user’s email. It’s easy to set up and doesn’t cost extra per message.

However, if someone has already hacked your email, you’re wide open.

So while email OTPs are okay for low-risk actions, they’re not ideal for high-stakes security.

3. Authenticator apps

Apps like Google Authenticator or Authy generate OTPs that refresh every 30 seconds.

These aren’t “sent” in the usual sense—the code lives inside the app on the user’s phone.

This method is way more secure than SMS or email, but it does require your user to install and set up an app.

It has a slight learning curve, but is great for power users and devs.

4. Push notifications

This one is becoming popular, especially with mobile apps.

Instead of sending a code, you send a push notification asking the user to approve or deny a login or transaction. It’s fast, seamless, and less prone to interception.

The main downside is that the user needs to first install your app and enable push permissions. But when it works, it’s slick.

Each of these 4 methods has its place. You can choose one, combine a few, or let users pick what works best for them.

Security isn’t one-size-fits-all, and OTP delivery shouldn’t be either. 

How does SMS OTP compare with other channels of OTP delivery?

Here’s how SMS stacks up against other popular OTP delivery methods like WhatsApp, email, and push notifications:

Criteria	SMS OTP	WhatsApp OTP	Email OTP	Push notification OTP
Delivery speed	Fast (within seconds)	Fast (within seconds)	Can be slower	Instant (if user is online)
Deliverability	Very reliable (most phones support it)	Reliable, but depends on WhatsApp setup	Sometimes delayed or goes to spam	Very reliable if app & permissions are set
Security	Moderate (can be intercepted)	Moderate to high	Low to moderate (email hacks happen)	High (harder to tamper with)
User experience	Simple and familiar for everyone	Smooth and familiar (for WhatsApp users)	Okay, but not very user-friendly	Good if they’re always on your app (just tap to approve)
Internet needed?	No	Yes	Yes	Yes
Cost to business	Moderate (per SMS charges apply)	Usually lower than SMS	Low	Low (after setup)
Best for	User login verification, payment confirmations, two-factor authentication (2FA), and reaching users with or without internet access	User logins, quick account verifications, or actions inside existing WhatsApp conversations	Suitable for account signups, newsletter confirmations, password resets, and low-risk actions.	Perfect for in-app approvals, sensitive transactions, device logins, and high-security actions

So, whichever one you choose, remember to prioritise user experience while implementing OTP authentication to ensure a smooth and secure login process. 

What are examples of OTP messages?

Here are some typical examples of OTP messages across different channels.

1. SMS OTP

Your verification code is 483921. Do not share it with anyone. Expires in 10 minutes.

2. WhatsApp OTP

🔐 Your OTP is 764320. It’s valid for 5 minutes. Please don’t share this code with anyone.

3. Email OTP

Subject: Your One-Time Code
Body: Use 998102 to log into your account.
This code expires in 15 minutes. If you didn’t request this, ignore the email.

4. Push Notification OTP

New login request from iPhone 15 in Dubai.
Tap to approve or deny.
[Approve] [Deny]

5. In-app OTP

To approve your $1,200 transaction, enter the OTP sent to your phone: 346581The key is to keep the message short, time-bound, and secure. Use phrases like “Do not share” and highlight the expiry window. And, personalise it with context (like device/location) when possible, to build trust.

Some interesting stats on OTP usage

Here are some interesting stats about OTP usage.

• 80% of hacking-related breaches are due to stolen or weak passwords. As Microsoft says, OTP-based 2FA can block 99% of these data breaches.
• 93% of enterprises now use OTPs as part of their user verification flow.
• Push-based OTPs are gaining traction, especially in industries where user experience matters (e.g., e-commerce, ride-hailing).
• The global OTP authentication market is expected to reach $20B+ by 2027, showing that adoption is still growing fast.

So, if your product involves logins, payments, or personal data, OTP should be part of your core security layer.

And, understanding how OTPs are generated is helpful if you’re building a custom flow or working with authentication APIs. 

How does OTP work? 

Here’s how an OTP works:

• For an OTP payment, a user initiates a login or transaction. Then the system generates a one-time password.
• The OTP is securely delivered to the user via SMS or email.
• To complete the authentication process, the user enters the OTP within a specific time limit. This OTP code authorizes the user to complete the transaction.

To do this, you need an OTP platform.

What are the different types of OTP algorithms?

There are two primary types of OTP generation algorithms:

1. TOTP (Time-based One-Time Password

• Based on the current time and a secret key.
• The OTP changes every 30–60 seconds.
• Commonly used in authenticator apps like Google Authenticator, Authy, etc.
• Highly secure as the code expires quickly, even if exposed.

2. HOTP (HMAC-based One-Time Password)

• Uses a counter-based system instead of time.
• Every time a user triggers an action (e.g., clicks login), the counter increases and a new code is generated.
• Less common today, but used in certain token systems where time sync is tricky.

If you’re integrating OTPs via a third-party provider, they often use TOTP by default. 

What is an OTP platform? 

An OTP platform is a service or software solution that lets you generate and send OTPs. 

The platform handles the generation and sending of the OTP (and all the technicalities that come with it), so you don’t have to do it yourself. 

An OTP platform includes the following components:

• A way to generate OTPs.
• A server-side application or a third-party service.
• A method of delivering OTPs to users. It could be via SMS or email. 
• A system that ensures you can access the secure system only with a valid OTP.
• A user management system that allows administrators to manage the system’s users and assign permissions and roles.

How can you set up OTP via SMS as a product owner or developer?

How do you set up OTP SMS?

You can create your own OTP SMS. Here’s a step-by-step guide on how to set up OTP for SMS, send OTP to phone numbers, and integrate OTP service into your website:

• Sign up with an OTP service provider: An OTP service generates unique temporary passwords and delivers them securely to users via SMS or email. You can use SMSCountry’s SMS API services for this.
• Customise SMS templates: Personalise your SMS templates on the platform to craft engaging and informative messages for OTP delivery.
• Obtain API credentials: Get the necessary API credentials from SMSCountry to establish a seamless connection between your application and its OTP service.
• Integrate OTP API: Integrate SMSCountry’s OTP API into your website or application, enabling seamless OTP generation and delivery.
• Define OTP rules: Set up specific OTP generation rules, such as length and expiration time, to meet your security requirements.
• Set up a reliable SMS delivery: Set up a reliable SMS delivery mechanism in your application to ensure OTPs are delivered promptly and correctly.
• Provide SIM card-less OTP options: Explore SMSCountry’s offerings to enable OTP generation without a SIM card, ensuring flexibility for your users.
• Understand the cost structure: Get familiar with SMSCountry’s pricing plans and determine if charges are associated with sending OTPs.
• Set up an OTP server: If required, follow the recommended guidelines to set up your own OTP server for enhanced control and customization.

Stick with me. There’s more to learn about OTPs.

How fast do OTP codes arrive?

Speed matters, especially when users are trying to log in or approve a transaction. Here’s how long OTPs typically take to arrive for different OTP channels.

Channel	Typical Delivery Time	Why It Takes That Long
SMS	3–15 seconds	Depends on telecom routes, carrier delays, or spam filtering.
WhatsApp	3–20 seconds (or longer)	Requires internet, but uses faster delivery APIs.
Email	5–30 seconds (or longer)	Slower due to email queueing, filters, or spam traps.
Push	Instant (1–2 seconds)	Sent via app’s native push system—fastest option.

If time-to-verify is critical (e.g., for fintech or crypto platforms), SMS, push or WhatsApp OTPs are ideal. But SMS remains the most universally accessible, especially where the internet isn’t guaranteed.

Why are OTPs safe?

From a technical perspective, OTPs offer a solid layer of protection because:

• They expire quickly. Most OTPs last between 30 seconds and 15 minutes, reducing exposure risk.
• They’re one-time only. Even if intercepted, they can’t be reused.
• They use secure generation algorithms like TOTP/HOTP that produce unpredictable codes.
• They’re paired with other session or device data (e.g., IP address, browser fingerprinting) for contextual security.
• They reduce password dependency, making brute-force and credential stuffing attacks harder to execute.

Of course, no method is 100% foolproof, especially if a user willingly shares the OTP. But as far as automated protection goes, OTP is one of the most effective tools out there.

 

What can you use OTP for? 

Besides understanding what OTP means and how OTPs work, knowing what you can use OTPs to do is essential. 

You can use OTP for the following:

• Enhancing the security of online accounts: You can use OTPs as an extra layer of protection against unauthorised access to online accounts, such as email, social media, healthcare or financial accounts.
• Verifying the identity of users: OTP is a reliable way to verify the identity of your customers when they log in to an account or access your system. This helps to prevent unauthorised access and protect sensitive data.
• Protecting against cybercrime: With OTP, you can protect your customers from cyber attacks such as phishing or brute force. It does this by making it harder for unauthorised users to access your accounts and systems.
• Completing online transactions: It helps you authenticate online transactions such as online banking. This protects you against fraud and ensures that your transactions are secure.

There’s more. Next, we’ll show you what your business stands to gain from OTPs.

“We were frustrated with Twilio and Alibaba’s SMS API services until we found SMSCountry via a quick Google search. SMSCountry provides fast OTP SMS delivery and great customer support. Much recommended” 

– Gaurav Aggarwal, Director, Kavya Digital Solutions

What are the benefits of one-time passwords?

Can you still recall what OTP means and how it works? 

Here are four benefits of OTP for your business:

• Security: There are possibilities for a personal data breach when handling online transactions. An OTP gives exclusive access to the account holder and minimises the risk of account misuse. 
• Difficult to predict: Unlike user-created passwords, OTPs are random characters. They are challenging to remember and have a time limit (sometimes less than 60 seconds).
• Uncomplicated to use: It is easy for your customers to access their OTP. Most of these passwords get delivered through SMS, WhatsApp or email. Your customers don’t have to juggle between different systems.
• Cuts down your IT support cost: The IT department handles complicated tasks such as forgotten or lost passwords. Using an OTP service provider saves time. OTPs eliminate the stress of dealing with cyberattacks and hackers. 

You have seen various ways your business can benefit from using OTPs. Let’s look at some industries where you can efficiently use OTPs.

Want to send fast and secure OTPs to delight your customers on WhatsApp? Get our WhatsApp messaging solution Today!

Which industries can benefit from one-time passwords?

Using one-time authentication codes is not limited to financial institutions. 

Several other industries make use of OTPs. These industries include:

• Events and entertainment industry to generate entry tickets. 
• Aviation industry for issuing online airline reservations, payments, and verifications.
• Social media sites and online apps to prevent fake login. 
• Healthcare industry for booking appointments. 
• Banks, finance apps, and other online transaction services. 
• Registration on government websites, apps, and other platforms. 

We have seen some of the industries where OTPs prove helpful. Let’s go right into what you need to send OTPs to your clients.

What’s the future of OTP? And why should you care?

Even OTPs are evolving fast.

Here’s what’s coming next, and what it means for you as a business owner, developer, or decision-maker.

1. Biometrics + OTPs combo

Ever unlocked your phone with your fingerprint or face? That’s biometrics. Now, imagine adding it to an OTP.

So, instead of just getting an OTP, the system also checks your face or fingerprint.

Why it matters: Even if someone steals your phone, they can’t log in unless they also appear to be you or have your fingerprint. It’s like having two locks on your door instead of one.

This combination is getting popular, especially in banking and finance. According to HyperVerge, more companies are pairing biometrics with OTPs to tighten security and reduce fraud.

2. AI-optimised OTP delivery

Sometimes, for so many reasons, OTPs may not get to the user fast, or at all. Annoying, right?

Now, AI is stepping in. It watches how people behave and their current network strength, and figures out which channel (SMS, WhatsApp, push, email) will reach you the fastest.

What it solves: You won’t waste time waiting. You get your OTP where you’ll see it quickly.

Platforms like Zixflow are already doing this, choosing the best route for each OTP based on past delivery success.

3. Passwordless logins (no more “Forgot Password” headaches)

In the near future, you won’t even need passwords.

OTPs will be the new key.

Imagine this: You open your app, it sends a push notification, and you tap “Yes, it’s me.” That’s it. You’re in.

What it solves: People hate remembering passwords. Businesses hate dealing with password resets. This solves both.

Microsoft is already leading the charge by making passwordless sign-ins the default.

5. OTPs + Blockchain (Think: Ironclad Security)

Blockchain isn’t just for Bitcoin. It’s also being used to build secure ID systems. Combine that with OTPs, and you get a login system that’s nearly impossible to fake or hack.

What it solves: If your business deals with sensitive info, like health data, legal records, or money, this could be your next big upgrade.

A recent study found that combining blockchain and OTPs can prevent tampering and make identity checks super secure.

If you’re building for scale or sensitive data use cases, it’s worth investing in an OTP system that’s adaptable, multi-channel, and ready for what’s next.That said, let’s dive into what you need to send OTPs to your clients today.

 

What do you need to send OTP? 

To send an OTP, you will need the following:

• A way to generate the OTP, such as a server-side application or a third-party service.
• A method of delivering the OTP to the user, such as SMS, WhatsApp or email.
• The phone number or email address of the user to send the OTP.
• Any additional information the system or service requires, such as the user’s login credentials.

By fulfilling these requirements, you can send an OTP to a user.

Improve the security of your business with OTPs

You now know how OTPs can work for your business and the benefits you derive from using OTPs in serving your clients.

It’s about time to leap. 

Choosing an efficient and reliable OTP service provider for your business can be difficult. That is why we created this article on the best OTP SMS providers.

Using SMSCountry is your best shot at premium OTP SMS service. We provide the best SMS routes, quick onboarding, and a dedicated account manager. 

Wait no longer. Request a demo or signup for free to get started.

Frequently Asked Questions About OTP

What is an OTP code? 

In simple terms, an OTP code is a unique password that you can use only once. 

They are usually four or six numeric digits.

This code enables you to gain a single login session. You can perform a transaction with your OTP on a computer or digital device. 

What is the full-form of OTP?

The full form of OTP is One-Time Password.

Who is the founder of OTP?

One-time passwords (OTPs) were first introduced by Leslie Lamport in 1981 as a method for securing computer systems.

What is OTP payment?

OTP payment is a secure payment method that requires a one-time password to complete a transaction.

How can I get OTP for WhatsApp?

The WhatsApp OTP is usually sent via SMS to the user’s registered mobile number. To get an OTP for WhatsApp, follow these steps:

• Sign-up for WhatsApp API solutions like SMSCountry WhatsApp API.
• Integrate the API, and you’re good to go.

How can I receive OTP?

You can receive OTPs via SMS, email, voice, or other means, depending on the specific implementation and requirements.

Is OTP always a number?

No, OTP is not always a number. While numeric codes are commonly used for OTPs, they can also include alphanumeric characters or even symbols, depending on the specific implementation and requirements.

How many types of OTP are there?

There are two main types of OTPs.

What are the two types of OTP?

 Hash-based one-time passwords (HOTPs) and time-based one-time passwords (TOTPs).

How many digits is an OTP?

An OTP is typically 4 digits long.

What is 6 digit OTP number?

A 6-digit OTP number is a one-time password that provides extra security for online transactions and is valid for single use.

How do I get an OTP email?

OTPs are usually sent via SMS, not email. However, if you are specifically looking for an OTP via email, you need to check if the service or platform you use supports email-based OTPs.

How do I use OTP on my phone?

To use OTP on your phone, you typically receive an SMS containing the OTP code. You then enter this code into the relevant application or website to complete the verification process.

Can you do online transactions without OTP?

Yes, it is possible to do online transactions without an OTP, depending on the specific platform or service you are using. However, OTPs are commonly used as an additional layer of security for online transactions.

How can I get WhatsApp OTP without a SIM card?

To receive an OTP without a SIM card:

• Use OTP apps like Google Authenticator or Microsoft Authenticator to receive OTP without a SIM card.
• Request a replacement SIM card from your carrier to access OTP messages.
• Explore online SMS verification services that offer virtual phone numbers for OTP reception.
• You can also use a SIM card via email.

What is an example of an OTP service?

SMSCountry is an example of an OTP service. SMSCountry provides an SMS gateway for OTP delivery, allowing you to send OTPs in less than 5 seconds in over 180+ countries. They also offer unique sender IDs and verified tags to enhance brand recognition and customer trust. SMSCountry is known for its fast bulk OTP service and secure transactions.

Which OTP is best?

Here are some of the most reliable OTP service providers:

• SMSCountry
• D7 Verify
• Shoutout OTP
• Nexmo Verify
• Telesign Voice Verify
• Twilio Verify Phone Number
• OpenOTP

How to set up an OTP server and integrate OTP service into your website

To set up and integrate OTP service to your website, follow these steps:

• Choose OTP server software that best fits your requirements and preferences for OTP authentication.
• Install the OTP server software using the instructions provided by the software company.
• Configure the OTP server settings according to your specific needs, such as authentication methods, token types, and user database configuration.
• Configure the remote access server for OTP to integrate it with the OTP server.
• Test the OTP server to verify that it functions correctly.
• Train your users on how to set up and use OTP tokens for authentication.
• Monitor and maintain OTP server performance. Apply updates and patches, and ensure proper backups to maintain functionality and security.

How is OTP verified?

OTP is verified using Hashed Message Authentication Code (HMAC) algorithm. The programme creates a unique code in the login layer and sends the exact match of the unique code to the verified user. The only way login is allowed is if the user enters the exact match code sent to the verified user.

What is a 6-digit OTP number?

A 6-digit OTP number is a one-time password composed of six digits.

What is an example of an OTP password?

An example of an OTP password is “123456”.

Is OTP a PIN number?

No, OTP and PIN are two different concepts. OTP is a one-time password used for authentication purposes, while a PIN (personal identification number) is a numeric password used for access control.

Where is OTP used?

OTP is used in various applications and systems for authentication and verification purposes, such as online banking, e-commerce, and two-factor authentication.

What is the most common 4-digit OTP?

The most common 4-digit OTP is “1234”.

What is the maximum digit of OTP?

The maximum digit of OTP can vary depending on the specific implementation and requirements. However, some OTP systems use 6 digits for added security

Can hackers intercept OTP?

Yes, although most hackers find it really hard to intercept OTPs. OTPs aren’t encrypted to a device but to a phone number. So, to intercept an OTP, a hacker has to do sim-hijacking, which is not an easy job.

How do fraudsters use OTP?

Fraudsters can exploit OTPs for their malicious activities. Here are some ways they do this:

• Phishing: Fraudsters can send deceptive emails or messages impersonating legitimate organisations. If you fall for this trick, you reveal your OTPs unknowingly.
• SIM swapping: SIM swapping is an identity theft where fraudsters gain control of your phone number and SIM card.
• Social engineering: Fraudsters can pose as customer support representatives or use other persuasive tactics. This way, they can manipulate you into providing OTPs.
• Malware attacks: They can plant malicious software on your device that can capture OTPs.
• Intercepting communication channels: Sophisticated attackers can intercept SMS or email channels to access OTPs intended for you.

How can you send OTP to your customers?

There are many ways you can send OTPs to your customers. You can send OTPs via SMS, email, or a specialised OTP app. 

Let’s explain what OTP text or SMS is and the others. 

• OTP text or SMS: You can send OTPs to your customer’s device via SMS (short message service) or WhatsApp. It is an easy and convenient way for customers to receive OTP.
• Voice OTP: A voice OTP is one you deliver to your customer via a voice call. This requires you to put a call through and spell out the digits.
• Email OTP: You can send OTPs to your customers through email. These types of OTPs are what we call Email OTP.

What is OTP on a website?

OTP on a website is a one-time authentication password that verifies users before they can log in. This helps prevent fake logins and protects user data from being hijacked.

Is OTP a PIN number?

No, OTP is not a PIN number. OTP stands for One-Time Password, which is a temporary code used for authentication. It differs from a PIN, a fixed numeric code for personal identification or access.

Is OTP always a number?

No, OTP is not always a number. While numeric codes are commonly used for OTPs, they can also include alphanumeric characters or symbols, depending on the specific implementation and requirements.

How is OTP verified?

OTP is verified using Hashed Message Authentication Code (HMAC) algorithm. The programme creates a unique code in the login layer and sends the exact match of the unique code to the verified user. The only way login is allowed is if the user enters the exact match code sent to the verified user.

Can hackers intercept OTP?

Yes, although most hackers find it really hard to intercept OTPs. OTPs aren’t encrypted to a device but to a phone number. So, to intercept an OTP, a hacker has to do sim-hijacking, which is not an easy job.

How do I send OTP to a mobile number?

To send an OTP to a mobile number, you can automate the process using an SMS provider API. The API will automate your OTP generation, delivery, and verification.

How do I send OTP for mobile verification?

You can leverage an SMS provider’s API to send an OTP for mobile verification. This API simplifies verification by automating OTP generation, delivery, and verification.

How can I send OTP via SMS for free?

You can send OTP via SMS for free using SMSCountry’s free credits. The free credits let you test the platforms’ speed and reliability.

How do I create an OTP?

To create an OTP for user verification in your app or website, you can leverage SMSCountry’s reliable OTP SMS delivery service that delivers your SMS in less than 5 seconds.

What countries have OTP?

OTP (One-Time Password) is widely used across countries as a security measure by banks, websites, and apps. It ensures account safety by generating unique passwords. It’s a common feature worldwide for safeguarding sensitive information.

Which app is used to send OTP?

Various apps and platforms can be used to send OTP (One-Time Password). Popular options include SMS service providers with OTP capabilities, authentication service providers, or even custom-built applications with OTP functionality. It ultimately depends on your specific requirements and the app or platform’s integration capabilities.

Which app can I use to order without OTP?

Apps like Amazon, Flipkart, and Uber Eats provide options to save your payment information securely, allowing you to place orders without OTP authentication.

Can OTP be sent via WhatsApp?

Yes, OTPs can be sent via WhatsApp. However, it is important to note that WhatsApp’s API does not currently support sending OTP messages directly to users. If you wish to utilize WhatsApp for OTP delivery, you must explore alternative methods, such as integrating SMSCountry’s WhatsApp API.

How can I create OTP in WhatsApp?

To create OTP functionality within WhatsApp, you would need to develop a custom solution like integrating an SMS provider like SMSCountry’s WhatsApp Business API.

How do I send bulk SMS with my phone?

You can send bulk SMS with your phone using a bulk SMS service provider’s mobile phone application. A good SMS provider’s mobile app is as good as their web and desktop platforms.

How to send OTP to a phone number

Whether you’re in India or any other country, you can send and receive OTPs for authentication purposes. Here’s a step-by-step guide on how to send an OTP to a phone number in India and other countries:

1. Select a reliable OTP service provider like SMSCountry that suits your requirements and offers reliable delivery and security features.
2. Generate a one-time OTP (One-Time Password) code that ensures secure authentication for the intended user.
3. Collect the phone number of the user to whom you want to send the OTP for verification purposes.
4. Initiate the OTP delivery process using the chosen service provider, ensuring prompt and accurate delivery to the specified phone number.
5. Notify the user about the sent OTP, providing clear instructions on how to verify it.
6. Verify the user’s OTP against the generated OTP to confirm their identity and grant access to the desired service or information.

How to send an OTP SMS (Step-by-step guide)

Sending OTP SMS isn’t complicated. 

It’s simple and easy.

You can implement OTP authentication for your application or platform with these easy steps.

Step 1: Choose a Reliable SMS Service Provider

The first step in sending OTP SMS is selecting a trustworthy service provider. Look for a provider with robust SMS delivery infrastructure, global coverage, and high deliverability rates. Ensure they have a simple API integration process to make the implementation hassle-free.

Step 2: Integrate the SMS API

Once you’ve chosen your SMS service provider, you must integrate their API into your application. The API documentation provided by the service provider will guide you through the integration process. Make sure to follow the instructions carefully and test the integration thoroughly before proceeding.

Step 3: Generate and Send the OTP

Now that you have integrated the SMS API, generating the OTP and sending it to the intended recipient is time. Typically, OTPs are random numeric codes with a limited lifespan. Generate a unique OTP for each user or transaction to enhance security.

Use the SMS API your chosen service provider provided to send the OTP to the user’s mobile number. Ensure to include the OTP code in the message and provide clear instructions on how to use it.

Step 4: Implement OTP Verification

After sending the OTP, you need to implement the verification process. Create a mechanism in your application to receive and validate the OTP entered by the user. Compare the user’s input with the generated OTP to confirm its authenticity.

Ensure you set a reasonable expiry time for the OTP to prevent abuse and enhance security. You can also consider adding additional layers of security, such as rate limiting or IP restrictions, to protect against malicious activities.

Step 5: Handle Failed OTP Attempts

In case of failed OTP attempts, allow users to resend the OTP. Include a user-friendly interface that allows them to request a new OTP easily. Additionally, you can implement logic to limit the number of failed attempts to prevent brute force attacks.

Step 6: Monitor and Improve

Once you have implemented OTP SMS functionality, monitoring its effectiveness and continuously improving it is essential. 

Keep track of the delivery rates, response times, and user feedback. Analyze any issues or bottlenecks and work closely with your SMS service provider to address them promptly.

Remember to prioritize user experience while implementing OTP authentication to ensure a smooth and secure login process.

How can you protect yourself from OTP fraud and theft

• Never share your OTP with anyone, including unsolicited callers or unknown individuals.
• Be cautious of suspicious emails, messages, or phone calls requesting your OTP.
• Keep your devices and software up to date with the latest security patches.
• Enable multi-factor authentication (MFA) whenever possible. It adds an extra layer of security.
• Keep an eye on your financial statements and account activities for unauthorised transactions.
• Report any suspected fraudulent activity to the appropriate authorities and your service providers.

How do fraudsters use OTP?

Fraudsters use OTPs to scam people by tricking them into providing the OTP or by intercepting the OTP to gain unauthorized access to accounts.

What is the maximum OTP request?

The maximum OTP request can vary depending on the specific implementation and requirements of the OTP system.

Does OTP need Internet?

No, OTPs can be delivered via SMS or other means that do not require an internet connection.

How can I get OTP on WhatsApp?

OTPs on WhatsApp are typically received via SMS or text message

How can I get OTP without a number?

OTPs are typically sent to a registered mobile number or email address, so it is not possible to receive OTPs without a valid phone number or email

Can someone use my OTP?

Yes, someone can gain unauthorised access to your OTP. They can potentially use it to authenticate themselves and gain access to your accounts or perform fraudulent activities.

Who invented OTP?

One-time passwords (OTPs) were introduced in 1981 by Leslie Lamport as a means to enhance computer system security.

Who provides OTP service?

There are reliable OTP service providers like SMSCountry, D7 Networks, SMS Global, and many others.

How much does OTP SMS cost in India?

The cost of OTP SMS in India can vary depending on the service provider and the volume of SMS messages. It is recommended to contact OTP service providers directly for pricing information

How can I send OTP in India?

Here is how to send OTP in India using SMSCountry:

• Sign up on SMSCountry’s website and get free SMS credits to test the platform in real-time.
• Choose the OTP service plan that suits your needs.
• Integrate SMSCountry’s OTP API into your application or system to generate and send OTPs via SMS.
• Use the API to send OTPs to users’ registered mobile numbers.
• Verify OTP by calling the SMSCountry verification API with the saved OTP ID and OTP code entered by the user.

Can I get OTP outside India?

Yes, you can receive OTP outside India if you have a registered mobile number or email address that can receive SMS or email messages.

What does an OTP message look like?

An OTP message typically contains a unique code or password that is sent to the user via SMS or email. It is usually a combination of numbers and/or letters.

How do I create an OTP SMS?

To create an OTP SMS, you must integrate with an OTP service provider like SMSCountry, which offers great SMS gateway services. They provide APIs that allow you to generate and send OTPs via SMS.

Can I create my own OTP?

Yes, you can create your own OTP system. To ensure security and reliability, it is recommended that you use an OTP service provider like SMSCountry.

Can I receive OTP via email?

Yes, you can receive OTPs via email, depending on the specific service or platform you use.

How can I get WhatsApp OTP without a SIM card?

One way to receive WhatsApp OTP without a SIM card is by using any online OTP app.

What is an alternative for SMS OTP verification?

There are various alternatives to SMS OTP verification, such as email-based OTPs, push notifications, or authenticator apps.

How do I make an OTP verification system?

To make an OTP verification system:

• Choose a reliable OTP service provider like SMSCountry that offers fast and secure OTP delivery in over 60+ countries.
• Sign up for an account on the SMSCountry website to access their OTP verification service.
• Integrate the OTP API. SMSCountry’s REST APIs can be integrated into your application or system to generate and verify OTPs.
• Generate OTPs using the SMSCountry API to generate OTPs for your users. You can customise the length and complexity of the OTPs as per your requirements.
• Send the generated OTPs to your users via SMS or voice call. SMSCountry offers high deliverability and low latency for OTP messages.
• After entering the received OTP code for verification, call the SMSCountry verification API with the saved OTP ID and OTP code entered by the user.
• Receive detailed reports by SMSCountry with easy-to-read detailed reports on OTP operations, deliverability, and efficiency.

How do companies send OTP?

Companies can send OTPs via SMS, email, voice, or other means, depending on the specific implementation and requirements.

What is an alternative to SMS OTP verification?

There are various alternatives to SMS OTP verification, such as email-based OTPs, push notifications, or authenticator apps.

How do I send OTP to a mobile number?

To send an OTP to a mobile number, you can automate the process by using an API from an SMS provider. The API will automate the OTP generation, delivery, and verification for you.

How do I send OTP for mobile verification?

To send an OTP for mobile verification, you can leverage an SMS provider’s API. This API simplifies the process of verification by automating OTP generation, delivery, and verification.

How to integrate OTP service to your website?

To integrate an OTP service into a website:

• Sign up on SMSCountry for FREE and get free SMS credits to test your OTPs.
• Obtain your API credentials.
• Use SMSCountry’s SMS API to send OTPs directly from your website.
• Implement code on your website to generate and send OTPs using the SMSCountry API.
• Prompt users to enter the OTP they received and validate it against the generated OTP.
• Grant access or complete the transaction if the OTP is valid.

How do I automate OTP SMS?

Follow these steps to automate OTP SMS:

• Research and choose an OTP service provider.
• Integrate the OTP service provider’s API into your application or system.
• Use automation tools like Selenium WebDriver or Appium to fetch the OTP from the SMS received on the user’s mobile device.
• Enter the fetched OTP into the relevant application or system using automation tools.
• Verify the OTP by calling the verification API provided by the OTP service provider.

How apps read OTP without permission

Some apps can read OTPs without permission by using accessibility services or exploiting vulnerabilities in the operating system or other apps. However, this is a security risk and can compromise the user’s privacy and security.

Can someone bypass OTP?

Yes, someone else can bypass your OTP. This can happen if your device is compromised or the OTP is intercepted during transmission. However, OTPs are still considered a reliable authentication method and are widely used for online transactions and account verification.

Can anyone read my OTP?

Yes. An OTP intercepted during transmission can be read by unauthorised parties. But secure OTP services, like SMSCountry, help to eliminate this.

How can I send OTP via SMS for free?

You can send OTP via SMS for free using SMSCountry’s free credits. The free credits let you test out the platforms so you can gauge their speed and reliability.

How do I create or set up an OTP?

To set up an OTP for user verification in your app or website, you can leverage SMSCountry’s reliable OTP SMS API delivery service that delivers your SMS in less than 5 seconds.

Who sends OTP from a bank?

Banks typically send OTPs to their customers for transaction verification. The OTP is usually sent via SMS to the customer’s registered mobile number.

What countries have OTP?

OTP (One-Time Password) is widely used across countries as a security measure by banks, websites, and apps.

Which app is used to send OTP?

Various apps and platforms can be used to send OTP (One-Time Password). Popular options include SMS service providers with OTP capabilities, authentication service providers, or even custom-built applications with OTP functionality. It ultimately depends on your specific requirements and the integration capabilities of the app or platform you choose.

Do you have to pay for OTP?

No, you do not have to pay for OTP. OTP is a free service provided by banks and other financial institutions to ensure secure transactions. The cost of OTP is borne by the service provider, and it is offered as a value-added service to customers. However, some telecom operators may charge a nominal fee for delivering OTP via SMS, but this is not a common practice.

Which app can I use to order that doesn’t require OTP?

Apps like Amazon, Flipkart, and Uber Eats provide options to save your payment information securely, allowing you to place orders without OTP authentication.

Which API is used for OTP verification?

OTP verification APIs are essential tools for developers to secure the authentication of applications and systems. Here are some examples of OTP verification APIs you must know:

• SMSCountry
• GetOTP API
• MessageCloud Verify API
• miniOrange OTP Verification API
• D7 Verify API
• ShoutOUT OTP API

Can OTP be sent via WhatsApp?

Yes, OTPs can be sent via WhatsApp. However, it is important to note that WhatsApp’s API does not currently support sending OTP messages directly to users. If you wish to utilize WhatsApp for OTP delivery, you would need to explore alternative methods, such as integrating SMSCountry’s WhatsApp API.

How can I create OTP in WhatsApp?

To create OTP functionality within WhatsApp, you need to integrate an SMS provider like SMSCountry’s WhatsApp Business API.

How do I send bulk SMS with my phone?

You can send bulk SMS with your phone using a bulk SMS service provider’s mobile phone application. A good SMS provider’s mobile app is as good as their web and desktop platforms.