REST API Reference

API Keys & Authentication

Manage test and live API keys, granular permissions, and security controls.

Docs Summary

  • What this page explains: Creating live vs test keys, permissions scopes, and key rotation.
  • Who should use it: Developers and system administrators managing security keys.
  • Related MailSend feature: API keys, test mode, granular scopes
  • Common use cases: Authenticating backend services, CI/CD automated testing
  • Related docs: Email API, SDK Reference, Webhooks

All requests to MailSend REST endpoints require a Bearer token API key. Keys can be generated with custom permissions and test mode flags.

Key PrefixEnvironmentDelivery Behavior
ms_live_ProductionDispatches real emails to recipient mailboxes.
ms_test_Sandbox / TestingSimulates validations and events without sending real SMTP emails.

You can revoke or rotate API keys instantly from Settings -> API Keys if a secret key is accidentally leaked.