Introduction

Retransmit is one API and one balance for sending email, SMS, and WhatsApp messages.

You do not create AWS, Twilio, or Meta accounts. Integrate once, load credit, and send. Retransmit handles the providers, routing, and delivery.

What you get

• Transactional email, including batches of up to 10,000 messages
• SMS with per-country provider routing and segment counts
• WhatsApp text, template, and media messages, with replies delivered to your webhooks
• A typed Node.js SDK: retransmit.dev on npm
• Per-message status and event history
• Signed delivery webhooks

How it fits together

Your application
      │  Authorization: Bearer rt_...
      ▼
Retransmit API  ──►  Email / SMS / WhatsApp
      │
      ▼
Retransmit infrastructure (SES, Twilio, Meta, ...)

Next steps

• Quickstart: send your first message.
• Email: single and batch sends, domains, marketing email.
• SMS: sender IDs, routing, segments, statuses.
• WhatsApp: templates, media, replies.
• API Reference: endpoints, authentication, errors.
• Webhooks: delivery events and signature verification.

Environments

Locally, run pnpm dev:api from the repository root. The API starts on port 3002 and the dashboard (pnpm dev:dashboard) on port 3001.