head to head
Resend vs Mailgun
Modern React-oriented API versus mature SMTP, routing, and high-volume tooling.
What matters for teams choosing a transactional API
Judged purely as an API. What the request contract guarantees on retry, how complete the webhook event coverage is, whether suppressions are readable and writable programmatically, and how much the message log retains when something needs debugging in production.
| Priority | Resend | Mailgun |
|---|---|---|
| Idempotency keys | Yes | No |
| Webhooks | Yes | Yes |
| Event stream | Yes | Yes |
| Operating since | 2023 | 2010 |
| Suppressions API | Yes | Yes |
| Best published rate per 1,000 | $0.35 | $0.70 |
| Batch sending | Yes | Yes |
| SDKs | node, python, go, ruby, php, rust, java, elixir, cli | node, python, go, ruby, php, java |
| Deliverability | Acceptable, but the deliverability track record is shorter than Postmark or SendGrid. Independent inbox-placement studies vary. Dedicated IPs are available on higher tiers. | Generally good, with deliverability monitoring tools available on higher tiers. Inbound routes and suppressions are battle-tested. |
For a transactional workload running high-frequency programmatic sends where a missed delivery is a product failure, Resend takes idempotency keys, best published rate per 1,000, and SDK breadth, while Mailgun takes operating track record. That ordering reflects this audience. Weigh the same table differently and the answer changes.
Side by side
| Feature | Resend | Mailgun |
|---|---|---|
| Webhooks | Yes | Yes |
| SDKs | node, python, go, ruby, php, rust, java, elixir, cli | node, python, go, ruby, php, java |
| Deliverability | Acceptable, but the deliverability track record is shorter than Postmark or SendGrid. Independent inbox-placement studies vary. Dedicated IPs are available on higher tiers. | Generally good, with deliverability monitoring tools available on higher tiers. Inbound routes and suppressions are battle-tested. |
| Tagline | Email API tightly coupled to React Email. | Developer-leaning email infra, owned by Sinch. |
| Free tier | 3,000/mo permanent, capped at 100/day, one domain | 100/day permanent free plan |
| Starts at | $20/mo for 50,000 emails | $15/mo for 10,000 emails (Basic) |
| Pricing model | tiered | tiered |
| API | Yes | Yes |
| SMTP | Yes | Yes |
| Templates | react-email | rich |
| React Email | Yes | No |
| Inbound | Yes | Yes |
| Multi-tenant | No | Yes |
| Idempotency | Yes | No |
| Dedicated IP | Yes | Yes |
| DX score | 8/10 | 7/10 |
| Best for | Early-stage React or Next.js product teams sending under 50k/mo. | Technical teams that want SMTP relay plus advanced routing. |
Resend
pros
- ›Idiomatic SDKs across major languages
- ›React Email integration is the smoothest of any provider
- ›Idempotency keys supported
- ›Clean dashboard and event log
cons
- ›Volume pricing is significantly higher than AWS SES at large volumes
- ›Founded 2023, so deliverability track record and incident history are still building
- ›No drag-and-drop template editor; non-React stacks get a thinner experience
- ›Free tier is capped at 100 sends a day, so a 3,000/mo allowance cannot absorb a launch spike
- ›January 2024 breach exposed email metadata, contacts, and encrypted API tokens for all users; message bodies were not reached
- ›Status page logged roughly ten incidents in the three weeks to 2026-08-01, mostly outside the sending path: dashboard, webhooks, domain verification, and automations
- ›Single-region historically; multi-region setup is newer
- ›Smaller support footprint than Twilio SendGrid or Sinch Mailgun
Mailgun
pros
- ›Strong SMTP relay support, useful when migrating off self-hosted Postfix
- ›Inbound routes with regex matching
- ›Validation and parsing tools available
- ›Sub-accounts for agency use cases
cons
- ›Overage pricing and plan differences need close review at scale
- ›Documentation is comprehensive but occasionally out of date
- ›No idempotency keys
- ›Sinch ownership has moved focus toward enterprise