Sonjj API Documentation

Most temp email APIs hand out disposable domains that signup forms reject — silently, before a single message is even attempted. SmailPro hands out real Gmail and Outlook addresses, which is why they actually land. One header to authenticate, three endpoints to operate, credits deducted only on a successful response.

This page is the overview — no endpoint listings, no code samples. Full API reference lives at the docs hub; pricing at sonjj.com/pricing.

Real Gmail and Outlook — Why It Matters

Services like Tempmail.com, Guerrilla Mail, and Maildrop hand out addresses on generic disposable domains. Salesforce, HubSpot, and most modern signup forms maintain blocklists of these domains — your test request is dropped before the email is even attempted. The failure is silent: no error, no bounce, just a form that never gets verified.

SmailPro works differently. The pool runs on 5,000+ real Gmail accounts and 3,000+ real Outlook accounts, with an average age of 6+ months. To Google, Microsoft, and every spam filter in between, these addresses look like regular users — because they are. The API rotates them so no single address takes repeated load. The pool also includes .edu.pl addresses for education-tier signups that reject standard consumer domains.

The result: 95% acceptance rate on real production signup forms, across workflows where a fake domain would have silently failed.

Three Calls. One Header. No SDK.

Authentication is a single X-Api-Key header. Copy the key from your my.sonjj.com dashboard, drop it in the header, and you're making requests. No OAuth flow, no SDK to install, no session cookie to maintain. Works with cURL, Python requests, Go's net/http, n8n HTTP node — anything that speaks HTTP.

The full flow is three calls:

1. Create an inbox — get back a real Gmail or Outlook address.
2. Poll the inbox for new messages — IMAP-synced every 5–10 seconds.
3. Read a message — get the full body or pull out the OTP directly.

The API is receive-only by design. It doesn't send mail — intentionally. Cleaner deliverability, no abuse vectors, predictable behavior for test automation and CI/CD pipelines.

View full API reference →

Pay for Results, Not Attempts

Credits are deducted only on a successful response. 4xx, 5xx, timeouts — nothing is charged. You pay for results, not attempts.

Per-call costs are transparent:

The base rate is $1.00 per 1,000 credits. At scale it drops to $0.30 per 1,000 credits — a 70% reduction. No monthly fees. Credits never expire, so buying ahead carries no risk.

The same credit balance covers SmailPro, YChecker, UGener, SMSer, StoreGmail, CardGener, and any other Sonjj product. One wallet, draw from it wherever you need it. More detail: How Sonjj credits work.

See all plans →

By the Numbers

• 400,000+ messages received
• 200,000+ inboxes created
• Sub-10 seconds OTP delivery — IMAP syncs every 5–10s
• 8,000+ real Gmail and Outlook accounts in active rotation
• 6+ months average account age — below spam filter radar
• 95% acceptance rate on production signup forms

Built and dogfooded by Sonjj — the same API powering internal testing across 7 products.

Where to Go Next

If you want to dig deeper before integrating:

• How SmailPro compares to Guerrilla Mail, Mailinator, and TempMail — side-by-side on domain trust, pricing model, and CI/CD fit
• SmailPro for QA, marketing, and security teams — team-level use cases and infrastructure details
• How Sonjj credits work across products — per-endpoint cost breakdown, expiry policy, and cross-product usage

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