The email API for developers
Send transactional email with one request. Manage templates without a redeploy. Switch providers without lock-in. Start free, go to production from $5/mo.
import { SenderKit } from "@senderkit/sdk";
const senderkit = new SenderKit({ apiKey: process.env.SENDERKIT_API_KEY! });
await senderkit.send({
template: "welcome_email",
to: user.email,
vars: { first_name: user.firstName },
});
import os
from senderkit import SenderKit
sk = SenderKit(api_key=os.environ["SENDERKIT_API_KEY"])
sk.send("welcome_email", "ada@example.com", vars={"first_name": "Ada"})
curl https://api.senderkit.com/v1/send \
-H "Authorization: Bearer $SENDERKIT_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"template": "welcome_email",
"to": "ada@example.com",
"vars": { "first_name": "Ada" }
}'
One endpoint, any language. The template lives in the dashboard — your code just names it.
An email API that gets out of your way.
One request to send
POST a template, a recipient, and your variables to /v1/send. That's the whole integration.
Templates without a deploy
Edit subject, body, and variables in the dashboard. Versioned, with one-click rollback.
No provider lock-in
Send built-in, or route through Amazon SES, Postmark, SendGrid, or SMTP. Switch with no code change.
Typed SDKs and a CLI
Type-safe SDKs for TypeScript, Python, and PHP, a CLI for CI, an MCP server for AI agents, and a REST API you can call from any language.
Webhooks for delivery
Get delivery, bounce, and complaint events pushed to your app so you can react in real time.
Start free, $5/mo to scale
A genuinely free tier with no credit card — 500 emails a month. Simple flat tiers as you grow: $5/mo Starter, $19/mo Pro.
A free email API, for real
Your first 500 emails every month are free — no credit card, no trial clock — and the free tier includes template management, the SDKs, and the CLI. It’s enough to run a side project or a small product’s entire transactional email on, and when you’re ready for production the Starter plan is $5/mo for a custom sending domain, unlimited templates, webhooks, and 5,000 emails a month. See the pricing page for current tiers.
Frequently asked questions
Is there a free email API?
Yes. SenderKit's email API is free to start — 500 emails a month with no credit card, including template management and the SDKs. When you're ready to grow, Starter is $5/mo (unlimited templates, a custom sending domain, 5,000 emails) and Pro is $19/mo (50,000 emails).
How do I send an email with the API?
Make an authenticated POST to https://api.senderkit.com/v1/send with a template name, a recipient, and your variables — or call senderkit.send() from one of the SDKs. The template itself is managed in the dashboard, so you don't ship HTML in your code.
Can I use my own email provider?
Yes. SenderKit can send on its own infrastructure or route through Amazon SES, Postmark, SendGrid, or raw SMTP — so there's no lock-in and you can switch providers without changing your send code.
Does the API do more than email?
Yes. The same API sends transactional SMS and push/web-push alongside email, so you don't need a separate product or integration per channel.
New to this? Start with what transactional email is, or compare SenderKit to SendGrid and Mailgun.
Send your first email in minutes
Start free, go to production from $5/mo. No credit card, no sales call. Add SMS and push from the same API when you need them.
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