How It Works

Verification in 4 Simple Steps

Integrate OTP verification into your application with just a few API calls.

Your App Calls Our API

Send a verification request with the user’s phone number. Our API generates a secure code and delivers it via SMS.

User Receives the Code

A 4-8 digit one-time password is delivered to the user’s phone within seconds via priority SMS routing.

User Enters the Code

The user types the received code into your application’s verification form.

Your App Verifies

Call our verify endpoint with the code. We confirm it’s valid, not expired, and hasn’t been used before.

Instant Delivery

Verify in Seconds, Not Minutes

Our optimized delivery network ensures OTP codes arrive within seconds. Voice fallback automatically kicks in when SMS delivery is delayed to certain carriers.

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Key Features

Enterprise-Grade Verification

Configurable Code Length

Set OTP codes from 4 to 8 digits. Balance security requirements with user convenience.

Expiration Control

Set code validity periods from 30 seconds to 30 minutes. Expired codes are automatically invalidated.

Rate Limiting

Built-in abuse prevention. Configure maximum attempts per phone number per time period.

Retry Logic

Automatic resend via alternative routes if initial delivery fails. Maximize verification completion rates.

Voice Call Fallback

If SMS doesn’t arrive, automatically call the user and read the code aloud via text-to-speech.

Real-Time Webhooks

Receive delivery status callbacks to track OTP delivery and verification events in real time.

Developer Experience

Built for Developers

RESTful API with comprehensive documentation and SDKs for popular languages.

RESTful API

Clean, well-documented REST endpoints. JSON request/response format. Standard HTTP status codes.

SDKs & Libraries

Official SDKs for Node.js, Python, PHP, Ruby, and Java. Get started with just a few lines of code.

Sandbox Environment

Test your integration without sending real messages. Simulate success, failure, and edge cases.

Copy-Paste Examples

Ready-to-use code examples for every endpoint. From basic verification to advanced flows with fallbacks.

Security

Fraud Prevention Built In

Rate limiting, IP whitelisting, and real-time monitoring protect your verification flows. Detect and block abuse patterns before they impact your users.

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Use Cases

Secure Every Critical Interaction

User Registration

Verify phone numbers at signup to prevent fake accounts and ensure valid contact information.

Login 2FA

Add a second authentication factor to your login flow. Protect accounts from unauthorized access.

Transaction Confirmation

Require OTP verification for high-value actions: payments, transfers, and account changes.

Password Reset

Secure account recovery with SMS-verified password resets. No more insecure email-only flows.

Frequently Asked Questions

How fast are OTP codes delivered?

In most cases, OTP codes are delivered within 3-5 seconds of the API request. Our platform uses priority routing for OTP messages to ensure the fastest possible delivery. We monitor delivery times in real time and automatically switch routes if latency exceeds acceptable thresholds. For time-sensitive verification flows, we recommend setting code expiration to at least 5 minutes to account for occasional carrier delays.

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