Drop-in compatible API · drop-in migration

Application email, on infrastructure you control.

The email your app has to send — password resets, receipts, alerts — through a Resend-compatible API on a mail server we operate. White-label multi-tenancy from the schema up. No third-party black box.

# Point your existing email client at our base URL — your code keeps working.
curl https://api.usermails.com/emails \
  -H "Authorization: Bearer um_live_••••" \
  -d from="you@yourapp.com" \
  -d to="user@example.com" \
  -d subject="Welcome aboard" \
  -d html="<strong>You're in.</strong>"
1 line
to migrate from Resend
Own MTA
Postfix we operate, not a reseller
Delivered
from the mail server — not just "sent"
100%
white-label, multi-tenant
Everything application email needs

Built for developers, owned end to end

A drop-in sending API, real delivery events from the mail server, and tenancy that agencies can resell.

Drop-in compatible API

Accepts the same payloads as the Resend SDK. Migrate by changing a base URL — no rewrite, no lock-in.

Authenticated sending

Guided SPF/DKIM/DMARC, one-click DNS on supported providers, and a verified-domain gate so you can't send as a domain you don't own.

White-label multi-tenant

Orgs → projects → keys from the schema up. Agencies and platforms resell email under their own brand and domain.

Signed webhooks

HMAC-signed email.sent, delivered, bounced, and complained events, retried with backoff.

Logs & observability

Recent message logs with a per-message event timeline — queued, sent, delivered, bounced, complained. Optional open/click tracking per domain.

Our own mail server

Sends go through Postfix we operate. Delivery status comes from that server, not from a shared third-party pool we can't see into.

Deliverability

"Sent" is not the metric. Delivered is.

We run the mail server, so a 250 from the receiving host becomes a delivered event — and a hard bounce or complaint auto-suppresses before the next send. Seed-list inbox-vs-spam tests and dedicated-IP warmup are on the roadmap; we don't pretend they ship today.

How deliverability works
  domain   acme.com            verified ✓
  SPF      aligned             
  DKIM     published           
  DMARC    p=quarantine        
  status   delivered           250 ✓
Pricing

Published rates. Billing isn't live yet.

Early access: no credit card. New accounts start on Free. Send caps below are already enforced; we are not charging the list prices yet.

Free
$0
  • 3,000 emails / mo (hard cap)
  • 1 domain · full API
  • Logs & webhooks
Pro
$18 / mo
  • 50,000 emails / mo (hard cap)
  • 10 domains · DKIM/DMARC
  • Signed webhooks
Scale
$80 / mo
  • 500,000 emails / mo (hard cap)
  • Custom domain + branding
  • 50 domains
White-label
$400+ / mo
  • Resell under your brand
  • Sub-accounts + usage rollups
  • 5M emails / mo (hard cap)

Ship your first email in five minutes.

Create a key, point your existing client at UserMails, send. Watch it land in your logs as delivered — or bounced, with a reason.