OTP API

One-Time Password
API

Send secure one-time passwords via SMS and WhatsApp. Perfect for two-factor authentication, account verification, and transaction confirmation.

Simple OTP Flow

Generate and send OTPs with just a few lines of code.

Send OTP
import Zavudev from '@zavudev/sdk';
import crypto from 'crypto';

const zavu = new Zavu('YOUR_API_KEY');

// Generate a secure 6-digit OTP
const otp = crypto.randomInt(100000, 999999).toString();

// Send via SMS (with WhatsApp fallback)
const message = await zavu.messages.send({
  to: '+1234567890',
  text: `Your verification code is: ${otp}. Valid for 10 minutes.`,
  channel: 'auto', // Will try WhatsApp first, fall back to SMS
  fallbackEnabled: true
});

// Store OTP hash with expiry for verification
// (Never store plain OTP - hash it!)

OTP Features

Secure Generation

Cryptographically secure OTP codes generated on our servers.

Instant Delivery

OTPs delivered in seconds via SMS or WhatsApp.

Auto Expiry

Configurable expiry times from 1 to 60 minutes.

Rate Limiting

Built-in protection against brute force attacks.

Multi-Channel

Send OTPs via SMS or WhatsApp with fallback.

Compliance Ready

GDPR and SOC 2 compliant infrastructure.

OTP Best Practices

Use 6-digit codes for balance between security and usability
Set expiry times between 5-10 minutes
Implement rate limiting (max 3 OTP requests per 10 minutes)
Hash OTPs before storing - never store plain text
Lock accounts after 5 failed verification attempts
Use cryptographically secure random number generation
Invalidate OTP after successful verification
Allow users to request new OTP (with cooldown)

Ready to Implement OTP?

Start sending secure one-time passwords in minutes. Perfect for 2FA, verification, and authentication flows.

OTP API | One-Time Password API for Authentication | Zavu | Zavu