SpacePost documentation

Send your first email

Node.js

send.ts

import { SpacePost } from "@spacepost/node";

const spacepost = new SpacePost(process.env.SPACEPOST_API_KEY);

const { data, error } = await spacepost.emails.send({
  from: "Acme <onboarding@test.spacepost.dev>",
  to: ["delivered@test.spacepost.dev"],
  subject: "Hello from SpacePost",
  html: "<p>It works.</p>",
});

if (error) throw new Error(`${error.name}: ${error.message}`);
console.log(data.id);

cURL

curl -X POST https://api.spacepost.dev/emails \
  -H "Authorization: Bearer $SPACEPOST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "Acme <onboarding@test.spacepost.dev>",
    "to": ["delivered@test.spacepost.dev"],
    "subject": "Hello from SpacePost",
    "html": "<p>It works.</p>"
  }'

Python

import os, requests

r = requests.post(
    "https://api.spacepost.dev/emails",
    headers={"Authorization": f"Bearer {os.environ['SPACEPOST_API_KEY']}"},
    json={
        "from": "Acme <onboarding@test.spacepost.dev>",
        "to": ["delivered@test.spacepost.dev"],
        "subject": "Hello from SpacePost",
        "html": "<p>It works.</p>",
    },
)
print(r.json())

Start here

QuickstartCreate a key, send a test email and verify a domain in five minutes.

Migrating from ResendChange one URL or one import. Everything else keeps working.

Send an emailEvery field, every limit, copy-pasteable examples.

Verify a domainAdd three DNS records and start sending from your own address.

WebhooksSigned events for delivery, bounces, opens and clicks.

SMTP relayUse SpacePost from Supabase, WordPress, Laravel, Django and Rails.

Why SpacePost

Drop-in for Resend

Same paths, same request and response shapes, same error format, same webhook signing. Point RESEND_BASE_URL at us and ship.

Priced for builders

3,000 emails free every month. Pro is €9 for 50,000 with €0.25 per extra thousand (excl. VAT). No per-seat fees, no sales calls.

Built on AWS SES

Amazon’s infrastructure and deliverability, without the AWS console. Easy DKIM, custom return path and per-team reputation isolation.

Made for agents too

An MCP server, a CLI with --json everywhere, an OpenAPI 3.1 spec and an llms.txt so your coding agent can use SpacePost correctly.

Tools

Node.js SDK@spacepost/node, Resend-compatible, zero dependencies.

CLIspacepost send, domains doctor, keys and more.

MCP serverLet Claude, Cursor and VS Code send and inspect email.

OpenAPIGenerate a client for any language.