Retransmit vs Resend
Resend is the polished default for developer email, with nine SDKs and a marketing suite. Retransmit is the small open stack you can read, self-host, and fund with prepaid credits instead of a card on file. Here is where each one wins.
By the Retransmit team. Last updated .
Retransmit builds one of the products compared here. Every competitor number was checked on the vendor's own site on the date above, and nothing on this page is paid placement.
Both products are transactional email APIs aimed at developers. Resend is a proprietary platform with a large feature surface: marketing broadcasts, audiences, automations, inbound email, and multi-region sending. Retransmit is deliberately narrower. It does transactional sending, batching, logs, and signed webhooks, its source is public, and its cloud runs on prepaid credits you can top up by bank transfer or mobile money. The tables below compare pricing, features, and deliverability line by line.
At a glance
The short version: pick Resend for breadth and polish, pick Retransmit for ownership and a pricing model with no subscription.
| Retransmit | Resend | |
|---|---|---|
| Positioning | Open email API you can run in our cloud or yours | Email for developers, transactional plus marketing |
| Source code | AGPL-3.0 on GitHub, MIT licensed SDK | Proprietary. Its React Email library is open source |
| Self-hosting | Yes, free forever | No |
| Free tier | Self-hosted is free with every feature | 3,000 emails a month, capped at 100 a day |
| Paid model | Prepaid credits, no subscription or seats | Monthly tiers from $20, plus opt-in overage |
| SDKs | Node.js, plus plain REST from any language | Node.js, PHP, Python, Ruby, Go, Rust, Java, Elixir, .NET |
| Best fit | Teams that want to own the stack or pay without an international card | Teams that want everything managed in one place |
Sources: Resend pricing
Pricing
Resend prices in monthly tiers. Free covers 3,000 emails a month with a hard cap of 100 a day and 3 domains. Pro is $20 a month for 50,000 emails, Scale is $90 for 100,000, and paid plans can opt into overage at $0.90 per 1,000 extra emails. Dedicated IPs are a $30 a month add-on on Scale, and SSO costs $150 a month.
Retransmit has no tiers. Self-hosting is free forever with every feature, no license key, and no phone-home. The cloud runs on one prepaid balance that only moves when a message does. You can fund it in your local currency, including bank transfer and mobile money, which matters in markets where a USD card is hard to get.
| Retransmit | Resend | |
|---|---|---|
| Free | Self-hosted, unlimited features, your own SES credentials | 3,000 emails a month, 100 a day, 3 domains |
| Entry paid | Top up prepaid credits, any amount | Pro, $20 a month for 50,000 emails |
| 100,000 emails a month | Prepaid, pay per send | Scale, $90 a month |
| Overage | None. Sending draws down the balance | $0.90 per 1,000 emails, opt-in, paid plans only |
| Dedicated IP | Not offered | $30 a month, Scale plan only |
| SSO | Not offered | $150 a month on Scale |
| Payment methods | Bank transfer, mobile money, local currency | Card |
Sources: Resend pricing
Sending features
Resend covers far more surface area today. Retransmit ships transactional sending, batching, and delivery tracking, and is honest about the rest: marketing tools, templates, and audiences are not built yet.
| Feature | Retransmit | Resend |
|---|---|---|
| Transactional API | Yes | Yes |
| Batch sending | Yes, up to 10,000 emails in one request | Yes |
| Scheduled sending | Not yet | Yes |
| Marketing broadcasts | Not yet | Yes |
| Templates and editor | Not yet | Yes |
| Contacts and audiences | Not yet | Yes |
| Automations | Not yet | Yes, metered per run |
| Inbound email | Not yet | Yes |
| SMTP relay | Not yet | Yes |
| Multi-region sending | No | Yes, four regions |
Webhooks and deliverability
This is where Retransmit punches above its size. Every send is queued and retried with exponential backoff, and every event is delivered to your endpoint with an HMAC-SHA256 signature over the timestamp and body, retried up to 8 times. Resend signs webhooks too and adds a managed deliverability layer: dedicated IPs with auto warm-up, blocklist monitoring, and deliverability insights.
| Retransmit | Resend | |
|---|---|---|
| Event webhooks | 9 event types, from sent to complained | Delivery, open, click, bounce, complaint events |
| Webhook signing | HMAC-SHA256, timestamped, 8 retries with backoff | Signed endpoints, per-plan endpoint limits |
| SPF and DKIM | Yes, records shown in the dashboard | Yes |
| Bounce and complaint handling | Automatic suppression | Automatic, dynamic suppression list |
| Dedicated IPs | No | Yes, $30 a month with auto warm-up, Scale only |
| Email logs | Full event history per email, by id | Logs with 30 day retention on self-serve plans |
Sources: Resend pricing
Self-hosting and ownership
Resend cannot be self-hosted. Retransmit's API, dashboard, queue, and SDK live in one public repository, and moving between cloud and self-hosted is a base URL change. Self-hosting brings your own Amazon SES credentials, so your quota and reputation are yours.
- Same SDK, dashboard, and webhooks in cloud and self-hosted mode.
- No license key and no phone-home when you run it yourself.
- Data stays on your servers when self-hosted, which simplifies compliance reviews.
Which one should you pick
- Pick Resend if you want marketing, automations, inbound, many SDKs, and a managed deliverability team behind you.
- Pick Resend if you need dedicated IPs or multi-region sending today.
- Pick Retransmit if you want to read and run the stack yourself, free, on your own SES account.
- Pick Retransmit if subscriptions do not fit how you pay, and prepaid credits by bank transfer or mobile money do.
- Pick Retransmit if your workload is transactional sending with batching and webhooks, and you do not want to pay for a suite around it.
Own your email stack. Send through the cloud with prepaid credits, or run the same code yourself for free.
Related resources
Best Resend alternatives in 2026
Four alternatives compared on price, features, and self-hosting.
Open source email API comparison
Retransmit, useSend, and Plunk, side by side.
Retransmit quickstart
Verify a domain, grab an API key, and send your first email in under five minutes.
Webhook docs
Nine event types, HMAC-SHA256 signatures, and a five line verification example.
Questions people ask
Is Retransmit a Resend alternative?
For transactional email, yes. Retransmit covers the core Resend workflow: verify a domain, send through an API or Node.js SDK, batch up to 10,000 emails in one request, and receive signed webhooks. It does not yet cover Resend's marketing, template, automation, or inbound features.
Is Resend open source?
The Resend platform is proprietary. Its React Email template library is open source, but you cannot self-host Resend itself. Retransmit is AGPL-3.0 on GitHub and the whole stack can be self-hosted for free.
What does Resend cost at 50,000 emails a month?
As of September 1, 2026, Resend's Pro plan covers 50,000 emails a month for $20, with opt-in overage at $0.90 per 1,000 extra emails. Retransmit's cloud has no monthly plan. You top up a prepaid balance and pay per send.
Can I migrate from Resend to Retransmit?
The API shapes are close. Both SDKs return a { data, error } result instead of throwing, and both use domain verification with SPF and DKIM. Point your sends at the Retransmit API, verify your domain, and re-create your webhook endpoints.
Does Retransmit support marketing emails?
Not yet. Retransmit is transactional-first: API sends, batches, logs, and webhooks. If you need broadcasts, audiences, or an email editor today, Resend, useSend, or Plunk are better fits.