SMS Verify API

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Screenshot of the TopMessage dashboard showing SMS Verify API requests, code delivery timelines, and real-time verification outcomes.
An elderly man looking pleased as he receives an SMS verification code delivered instantly through the TopMessage SMS Verify API.
An elderly man checking his phone while opening an SMS code sent via the TopMessage SMS Verify API to confirm his taxi booking.
A woman reviewing a secure banking verification SMS sent through the TopMessage SMS Verify API to confirm her account login.
A woman interacting with her phone while completing a secure two-step SMS verification process powered by the TopMessage SMS Verify API

Secure SMS Verifications

Whether you’re switching SMS providers or sending your first verification SMS to app users, TopMessage's SMS Verify API ensures secure verification and supports your growth.

Integrate the SMS Verification API into your app or website to instantly block 99% of spam users.

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SMS Verify API

SMS Verification API for Easy User Verification

Screenshot of TopMessage SMS OTP Codes Generation page.

One-Time Password (OTP) Generation

With TopMessage SMS OTP API, generate, send, and verify OTP codes via SMS. Simply define the code length and expiry, and our API manages everything seamlessly.

Screenshot of TopMessage SMS code delivery page.

Secure SMS Delivery

An SMS Verification Service securely delivers a unique, time-sensitive code directly to each user’s phone, ensuring fast and reliable authentication.

Screenshot of the TopMessage interface displaying real-time SMS verification codes being generated, delivered, and validated instantly.

Code Verification

TopMessage SMS OTP API instantly validates entered codes, confirming verification when correct and rejecting them automatically if they don’t match.

Screenshot of the TopMessage dashboard displaying SMS code conversion statistics, including verification success rates, delivery performance, and failure reasons.

Code Conversion Rate

Monitor every verification SMS, measure conversion rates, and use the insights to optimize your process.

FAQs

What is the SMS Verify API and how does it work with TopMessage?

The SMS Verify API is a service provided by TopMessage that allows you to generate, send, and validate one-time passwords (OTPs) for user verification. You integrate the API into your application or website, select the SMS channel, and TopMessage handles OTP creation, delivery, and verification automatically. This enables secure, real-time user authentication without building separate systems.

How can I generate SMS OTPs for user verification?

Using TopMessage SMS Verify API, you can generate OTP codes by specifying parameters such as code length and expiration time. Once configured, the API automatically generates the OTP and delivers it to the user’s phone via SMS. The same API can then verify the entered code and confirm or reject it.

What security features are available for the SMS Verify API?

The SMS Verify API uses time-based, single-use OTPs to ensure secure user verification. It also automatically rejects invalid codes and includes rate limiting to prevent abuse

How does the retry mechanism work for SMS verification?

If a user doesn’t receive or enters an incorrect OTP, the SMS Verify API allows controlled retries. Each retry generates a new OTP, ensuring previous codes are invalid while maintaining secure verification.

How can I use the SMS Verify API for secure user authentication?

Use the SMS Verify API to secure user authentication. OTPs are sent, verified automatically, and only valid entries are approved, preventing unauthorized access.

SMS Verification API to Verify Users

Ensure Secure SMS Verification with TopMessage's Verify API.

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