Free APICommsAPI keyOfficial

Resend

Developer-first transactional email with a clean REST API and React email support

Resend is a transactional email API built for developers, with a single POST endpoint to send HTML, text, or React-rendered emails. It handles domains, DKIM/SPF, webhooks, and delivery analytics. The free tier sends real production email, not just sandbox.

View docs Get an API key

Free tier

Free forever: 3,000 emails/month, capped at 100/day, 1 custom domain, no card

Rate limits

Default 2 requests/second on the send API; free plan hard-capped at 100 emails/day

Auth

API key

Base URL

https://api.resend.com

What you'd build with it

Send password-reset, magic-link, and onboarding emails from an AI agent or app
Render React email templates and dispatch them programmatically
Trigger notification emails as the final step of an automation workflow
Test without a verified domain using [email protected] / [email protected]

Key endpoints

POST/emailsSend a single transactional email (html, text, or React)
POST/emails/batchSend up to 100 emails in one batched request
GET/emails/{id}Retrieve the status of a previously sent email
POST/domainsRegister a sending domain to get DKIM/SPF records

Members

Members get the runnable recipe

Create a free account Sign in