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OTP & 2FA SERVICE

Military-GradeAuthentication Security

Secure your applications with enterprise-grade OTP and two-factor authentication. Protect user accounts with industry-leading security standards.

Bank-Level Security

SOC 2 Type II & GDPR compliant

Instant Delivery

Sub-second OTP delivery globally

Developer First

Simple API, comprehensive SDKs

CORE FEATURES

Advanced Authentication Features

Everything you need to implement secure authentication in your applications

Multi-Factor Auth

Multiple verification methods

SMS, email, voice, and authenticator apps

Time-Based OTP

TOTP support

30-second codes that auto-expire

Counter-Based OTP

HOTP support

Event-based codes for special operations

Instant Delivery

Sub-second latency

Global delivery network

Mobile First

Mobile-optimized

Responsive delivery methods

Email OTP

Email verification

HTML templates and branding

API Keys

Secure API access

Rotating keys and permissions

Compliance

Enterprise ready

GDPR, SOC 2, HIPAA compliant

99.9%
Delivery Rate

Guaranteed OTP delivery

< 1s
Verification Time

Instant validation

0
Security Breaches

Zero successful attacks

VERIFICATION METHODS

Multiple Verification Channels

Choose the right verification method for your users and use case

SMS OTP

Text message verification

Features
Global delivery
Instant delivery
99.9% success rate
Best For
User loginAccount recoveryTransactions

Email OTP

Email verification

Features
HTML templates
Branding control
Delivery tracking
Best For
Account creationEmail verificationNotifications

Voice OTP

Phone call verification

Features
Multi-language
Text-to-speech
Call recording
Best For
High-security accessElderly usersBackup method

TOTP

Time-based OTP

Features
Google Authenticator
Authy
30-second expiry
Best For
App loginVPN accessAdmin panels

WhatsApp OTP

WhatsApp verification

Features
Instant delivery
Rich media
Interactive
Best For
Mobile appsYoung usersInternational users

Push OTP

Push notification

Features
No typing required
Instant approval
Biometric
Best For
Mobile bankingHigh-value transactionsCorporate access
Multi-Method Support

Fallback and Backup Methods

Implement multiple verification methods and automatically fall back if primary method fails. Users can choose their preferred verification channel.

SECURITY FIRST

Bank-Level Security Infrastructure

Built with security-first principles to protect your users and data

Certified

End-to-End Encryption

Military-grade AES-256 encryption for all OTPs

Certified

Rate Limiting

Prevent brute force attacks with intelligent rate limits

Certified

Zero-Knowledge Proofs

Never store OTPs in plain text

Certified

IP Geolocation

Block suspicious locations automatically

Key Rotation

Automatic API key rotation and expiration

Dedicated Tenancy

Isolated infrastructure per enterprise

Certified

Global Compliance

GDPR, CCPA, HIPAA compliant

Certified

Penetration Testing

Regular third-party security audits

Certified and compliant with industry standards

SOC 2
Compliant
GDPR
Compliant
HIPAA
Compliant
ISO 27001
Compliant
PCI DSS
Compliant
IMPLEMENTATION EXAMPLES

Secure Your Applications

See how to implement OTP and 2FA in common scenarios

Authentication

User Login

Secure user login with 2FA

POST /v1/otp/send
{
  "phone": "+1234567890",
  "channel": "sms",
  "purpose": "login"
}

POST /v1/otp/verify
{
  "phone": "+1234567890",
  "code": "123456"
}
Transactions

Payment Verification

Verify high-value transactions

POST /v1/otp/send
{
  "phone": "+1234567890",
  "channel": "whatsapp",
  "amount": "500.00",
  "merchant": "Example Store"
}

// User receives: 
// "Approve $500.00 payment 
// to Example Store? Code: 654321"
E-commerce

Order Confirmation

Confirm purchases with OTP

POST /v1/otp/send
{
  "email": "user@example.com",
  "channel": "email",
  "order_id": "ORD-12345",
  "template": "order_confirm"
}
Enterprise

Admin Access

Secure administrative panel access

POST /v1/otp/send
{
  "user_id": "admin_123",
  "channel": "totp",
  "permissions": ["admin", "billing"]
}

// User authenticates via 
// Google Authenticator app
Additional Use Cases
Account Recovery
Device Setup
Email Verification
API Access

Secure Your Application Today

Join thousands of developers who trust Sendexa for enterprise-grade authentication

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1,000 OTPs/month
No Setup Fees
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Trusted by financial institutions and enterprises worldwide