The developer email API that never slows you down or breaks staging
Clean REST endpoints, port 587 ESMTP submission, type-safe SDKs, and automated recipient allowlists to safeguard domain reputation from day one.
Drop into your application in under 60 seconds
Native typed interfaces with zero unnecessary dependencies. Built for standard fetch and modern edge runtimes.
curl -X POST "https://api.sadasend.com/emails" \
-H "Authorization: Bearer $SADASEND_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"from": "notifications@yourdomain.com",
"to": "developer@example.com",
"subject": "Deploy Alert: v2.4.0 Live",
"html": "<p>Build <strong>#1042</strong> successfully deployed to production.</p>",
"tags": ["ci", "deployments"]
}'Pure HTTP REST endpoint with JSON payloads, low latency, and predictable HTTP status codes.
Engineered for high deliverability and zero incident risk
Every layer from edge connection pooling to per-key rate limits is designed to keep critical transactional dispatches fast, reliable, and contained.
Zero-Dependency REST & SMTP
Connect via standard POST /v1/emails or standard Port 587 ESMTP with STARTTLS in any programming language.
Per-Key Domain Allowlists
Lock staging and preview branches to internal test domains so test emails never spam real customers.
Automatic Deliverability Safeguards
Pre-flight DKIM, SPF, and DMARC verification prevents sending from unauthenticated domains and stops delivery drops.
Real-Time Webhook Outbox
Receive immediate delivery, open, click, bounce, and complaint events with cryptographic HMAC signatures.
Clean Idempotency Keys
Include Idempotency-Key headers on requests to prevent duplicate sends during transient network retries.
RFC 8058 List-Unsubscribe
Automatic HTTPS and mailto one-click unsubscribe headers injected on outbound email streams.
SadaSend vs Legacy Providers (SendGrid / Mailgun)
Compare developer-first email infrastructure against legacy enterprise platforms.
| Feature & Capability | SadaSend | Legacy Providers (SendGrid / Mailgun) |
|---|---|---|
| REST API call | One HTTP round trip, then queued | 180 - 350ms |
| Per-Key Staging Allowlists | ||
| Hosted MCP Tool Integration | ||
| Dedicated IP Surcharge | $0 / included on Pro | $89.95 / mo |
| Silent 202 Drops | 0 (Strict Statuses) | Common failure mode |
| Monthly Free Sends | 6,000 forever | 100 / day or trial |
Start with 3,000 emails every month at zero cost
No artificial paywalls on security. Unlike legacy providers that reserve recipient allowlists or dedicated IP pools for high enterprise tiers, every SadaSend account receives full safety controls from day one.
Everything you need to know about email API for developers
Clear, transparent answers on deliverability, API authentication, and rate limits.
Related developer guides and architectural tutorials
Explore step-by-step production implementation blueprints, benchmarks, and protocols.
REST API Reference & Endpoints
Complete REST API reference for sending emails, managing API keys, tracking delivery events, and configuring recipient allowlists with low latency.
Official Client SDKs (TypeScript & Python)
Official zero-dependency client SDKs for SadaSend. TypeScript and Python packages are live on npm and PyPI with typed results and auto-idempotency.
SMTP relay & framework integrations
Connect existing applications, WordPress, Supabase, Laravel, Django, and Nodemailer to SadaSend via standard SMTP relay with zero code changes.
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