Eliminate Supabase Auth 429 rate limits with dedicated custom SMTP relay
Default Supabase Auth throttles projects to 30 emails per hour on shared infrastructure. Connect SadaSend port 587 SMTP in 60 seconds to unlock high deliverability and zero hourly caps.
Drop into your application in under 60 seconds
Native typed interfaces with zero unnecessary dependencies. Built for standard fetch and modern edge runtimes.
SMTP_HOST="smtp.sadasend.com"
SMTP_PORT=587
SMTP_USER="api"
SMTP_PASS="YOUR_SADASEND_API_KEY"
SMTP_ADMIN_EMAIL="auth@yourdomain.com"
SMTP_SENDER_NAME="Your SaaS Team"
# Enable STARTTLS security: Checked (Port 587)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 Hourly 429 Throttling
Bypass the default 30-email/hour shared Supabase rate limit. Deliver unlimited signup confirmations and magic links with burst capacity.
Instant Port 587 STARTTLS
Drop-in compatibility with standard SMTP settings in Supabase Cloud dashboard. No code changes or custom auth workers needed.
Custom Domain DKIM & SPF Alignment
Send from auth@yourdomain.com with 100% DKIM and SPF verification, ensuring login emails never land in user spam or promo tabs.
Real-Time Delivery Logs & Bounces
Inspect exact message delivery states, bounce reasons, and open rates in the SadaSend dashboard for every Supabase auth dispatch.
SadaSend vs Default Supabase Auth Email
Supabase default email is intended strictly for development and throttles at 30/hour. SadaSend provides production-grade deliverability.
| Feature & Capability | SadaSend | Default Supabase Auth Email |
|---|---|---|
| Hourly Dispatch Limit | Unlimited (Burst safe) | 30 emails per hour strict |
| Custom Sender Domain (From:) | auth@yourdomain.com | noreply@mail.app.supabase.io |
| Dedicated Deliverability IP Pools | ||
| Detailed Delivery Audit Logs |
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 Supabase SMTP
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.
SMTP relay & framework integrations
Connect existing applications, WordPress, Supabase, Laravel, Django, and Nodemailer to SadaSend via standard SMTP relay with zero code changes.
REST API Reference & Endpoints
Complete REST API reference for sending emails, managing API keys, tracking delivery events, and configuring recipient allowlists with low latency.
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