Transactional API

Lightning-Fast Transactional Email API

Ensure your users never wait for a verification code, reset password, or purchase receipt.

Sub-Second Delivery for Critical Messages

When a user registers on your application or requests a password reset, every second of delay reduces engagement and conversions. 171mails routes transactional messages through dedicated priority lanes with 99.9% delivered within 1.5 seconds.

Features for Developers & Product Teams:

  • Dedicated Transactional Queues: Zero interference from promotional blasts or scheduled marketing bursts.
  • Real-Time Delivery Webhooks: Receive immediate JSON payloads for delivery confirmations, opens, bounces, and failures.
  • Multi-Port Redundancy: Connect across standard ports (587, 465, 2525) with automatic fallback.
  • TLS 1.3 Security: Full end-to-end transport layer security protecting sensitive customer data.
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