Use Case

Secure 2FA Code Delivery

Send 2FA codes via email for secure authentication. Time-limited OTPs with instant delivery.

Why use Unosend for two-factor authentication emails?

Instant delivery (<2 seconds)
Time-limited codes
Works with any auth library
High security priority

Quick implementation

send-two-factor-auth.js
const otp = Math.floor(100000 + Math.random() * 900000);

await unosend.emails.send({
  from: 'security@yourapp.com',
  to: user.email,
  subject: 'Your verification code: {{code}}',
  template_id: 'tmpl_2fa',
  variables: {
    code: otp.toString(),
    expires_in: '10 minutes'
  }
});

Frequently asked questions

How fast are 2FA emails delivered?

2FA emails are prioritized and delivered in under 2 seconds for a seamless login experience.

Is email-based 2FA secure?

Email 2FA adds security over passwords alone. For higher security, consider TOTP apps alongside email.

Can I rate limit 2FA requests?

Yes, implement rate limiting on your end. Our API handles the delivery reliably.

Related use cases

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Send secure password reset emails instantly. Time-limited tokens, branded templates, and guaranteed delivery.

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Email Verification

Send email verification links to confirm user accounts. Reduce fake signups and improve deliverability.

Ready to send two-factor authentication emails?

Start sending in minutes with 5,000 free emails per month.