Two-Factor
Authentication
Protect user accounts with SMS-based two-factor authentication. Send OTP codes via SMS or WhatsApp for secure login and transaction verification.
Why Two-Factor Authentication?
Without 2FA
- xPasswords can be stolen via phishing
- xData breaches expose credentials
- xWeak passwords are easily guessed
- xAccount takeover is straightforward
With 2FA
- Stolen passwords alone are useless
- Real-time verification required
- Attackers need access to user's phone
- 99% of account attacks blocked
Easy Implementation
Add 2FA to your login flow in minutes.
import Zavudev from '@zavudev/sdk';
const zavu = new Zavu('YOUR_API_KEY');
// After password verification, send 2FA code
async function send2FACode(phoneNumber: string) {
const code = Math.floor(100000 + Math.random() * 900000);
await zavu.messages.send({
to: phoneNumber,
text: `Your login code is: ${code}. Valid for 5 minutes.`
});
// Store hashed code with 5 min expiry
return hashAndStore(code, phoneNumber, 300);
}
// Verify the code entered by user
async function verify2FACode(phoneNumber: string, code: string) {
const storedHash = await getStoredHash(phoneNumber);
return verifyHash(code, storedHash);
}Benefits of SMS 2FA
Account Protection
Add an extra layer of security beyond passwords to protect user accounts.
Universal Access
SMS works on any phone - no app installation required.
Easy Integration
Simple API to add 2FA to any login or sensitive action.
Compliance Ready
Meet PCI-DSS, HIPAA, and other security compliance requirements.
When to Use 2FA
Login Verification
Require 2FA code after password entry for secure login.
Transaction Confirmation
Verify high-value transactions with a second factor.
Account Changes
Confirm password changes, email updates, or profile modifications.
New Device Login
Require verification when users log in from new devices.
Secure Your Users Today
Implement two-factor authentication in minutes. Protect your users from account takeover with SMS OTP codes.