Resend
A developer-focused email API with a React-based email-templating workflow (React Email).
A developer-first email API from the React Email team, with a lovely DX. The default transactional email for indie and AI-built apps; React Email makes templates painless.
Resend is an email API built for developers, from the team behind React Email. You send transactional and marketing email over a clean API, and compose the emails themselves as React components instead of wrestling with table-based HTML. It has become a default for indie and AI-built apps for good reason.
Start with this
import { Resend } from 'resend';
const resend = new Resend(process.env.RESEND_API_KEY);
await resend.emails.send({
from: 'you@yourdomain.com',
to: 'user@example.com',
subject: 'Welcome aboard',
html: '<p>Thanks for signing up.</p>',
});The take, for AI builders
For people building with AI, Resend is the email layer that just works: a small API surface an agent can wire up correctly in one shot, and React Email means templates are components you can actually read and edit. The free tier is enough to launch on. Watch the sending limits as you grow, and warm up a real domain before you rely on it for anything important.
When to reach for it
✓ Good fit
- Transactional email — sign-ups, receipts, password resets
- You want to author emails as React components
- Indie or AI-built projects that need email wired up fast
✕ Not for
- High-volume bulk marketing at scale (weigh dedicated ESPs)
- You need a full marketing-automation suite, not just sending
Alternatives
Deliverability-obsessed and battle-tested when an email absolutely must land.
If you only need to receive form submissions, not send email.
Related in Backend & data
Algolia
A hosted search API delivering fast, typo-tolerant, relevant search-as-you-type.
- search
- api
- hosted
Search that feels instant and forgives typos, as a hosted API — the gold standard for site and app search. Brilliant DX; costs climb with scale, so watch the meter.
Visit ↗Appwrite
An open-source backend platform with auth, databases, storage, functions and realtime, self-hosted or cloud.
- baas
- open-source
- self-hostable
An open-source Firebase alternative with auth, databases, storage, functions and realtime. The pick when you want Firebase's breadth without the lock-in.
Visit ↗Auth0
An identity-as-a-service platform (an Okta company) with authentication, SSO and MFA for applications.
- auth
- identity
- enterprise
The enterprise identity standard — social, SSO, MFA, the lot. Rock-solid and feature-deep; pricing climbs steeply once you need enterprise connections.
Visit ↗