Resend
Transactional email API built for developers, with React email templates.
Resend does one job well: sending transactional email from an app without fighting a legacy ESP dashboard. Templates are React components, the API is small, and deliverability tooling is visible rather than buried.
Domain verification with SPF, DKIM and DMARC is still on you, that, not the API, is what determines whether your mail reaches the inbox.
What it's genuinely good at
- Clean API with excellent docs
- React Email templates version-control nicely
- Free tier covers side projects
- Clear deliverability and bounce insights
Where it falls apart
- Marketing-campaign features are thin
- Free tier daily caps are low
- You still must configure DNS correctly
Alternatives to Resend
Who should use Resend
- Signup, OTP and receipt emails from an app
- Side projects needing reliable email fast
- Teams that want templates in the repo
What it costs
Free tier around 3,000 emails/month with daily caps; paid plans from about $20/month for 50,000 emails.
Frequently asked
Why do my emails go to spam?
Almost always missing or wrong SPF/DKIM/DMARC records, or sending from a brand-new domain with no reputation.
Can I send marketing campaigns?
Possible, but dedicated marketing platforms handle segmentation and unsubscribes far better.