We build the email layer products ship on
Every product sends email: receipts, resets, invites, digests. And on most teams it is the least-loved part of the stack, wired up once, then ignored until a bounce spike or a spam-folder complaint forces someone to care.
SendSignal exists because that moment deserves better tooling. We put the sending API, the delivery evidence, and the deliverability diagnostics in one place, so the person on call can answer “what happened to this email?” without stitching together three vendors and a DNS lookup.
Delivery runs on Amazon SES infrastructure. The product is everything around it: the API, the console, and the judgment about what matters when something goes wrong.
What we believe
- Diagnose, don't scold. When a message bounces or a domain fails authentication, the product's job is to show you exactly what happened and what to change, not to lecture you about best practices.
- The surface isn't an upsell. Webhooks, suppression management, test mode, and the full observability surface ship on every plan, including the free one. Paid plans buy volume, not visibility.
- No overage surprises. When you hit your quota, sending pauses. Your card is never the pressure-relief valve for a runaway loop.
- Everything after hello-world. Most email APIs optimize the first five minutes. We care about month six: the bounce spike, the DMARC rollout, the migration, the audit.
Three surfaces, one product
Transactional and marketing sends, audiences, and inbound parsing behind one clean REST surface with SDKs for TypeScript, Python, and Go.
Every message's full delivery timeline: accepted, delivered, bounced, complained, opened. Built for debugging, not for dashboards.
A free suite of deliverability tools: SPF, DKIM, DMARC, and BIMI checks, DNSBL status, header analysis. Open to everyone, account or not.
Want to talk to the people building it? Contact us or follow along on the blog.
Start sending in minutes
3,000 emails a month free, a real test mode, and a console that shows you exactly what happened to every message.
No credit card required.