04Verify
Email address verification, without ever sending a message.
Syntax, disposable domain, MX records, then an SMTP dialogue cut before anything is sent. Four verdicts, each with its reason — never an opaque score.
https://verify.rankfabrik.com
online
Run it where you already work. Billed per address settled returned — nothing for empty results.
01What sets this service apart
Four verdicts, not a score
valid, invalid, risky, unknown — and a code that says why: no such mailbox, catch-all domain, disposable, no MX. You decide on the reason, not on a 73 out of 100.
Nothing is ever sent
The SMTP dialogue stops at RCPT TO, before any data. The recipient sees nothing, their inbox receives nothing. Microsoft 365 domains go through the identity API, no SMTP.
An unsettled address isn't billed
On a batch, only addresses actually settled count. If the time budget runs out, truncated: true says so and the remaining addresses cost nothing.
The fast mode exists, and it's named
sonder=false stops at the MX records: faster, more cautious verdict. You pick the trade-off; it isn't picked for you in silence.
02A real response
What you read before importing
The completude block arrives with every response. For the
fields that matter, it gives the share of results where they are
actually filled.
An empty field stays empty. No value is approximated, inferred from another field, or reconstructed by a language model.
curl -H "X-Cle-API: YOUR_KEY" \
"https://verify.rankfabrik.com/verifier-lot?..."03Routes
| Route | What it returns |
|---|---|
/verifier-lot | Up to a hundred addresses in one call, deduplicated, with a per-verdict summary. |
/verifier | One address, its verdict and its reason. The sample to judge on a real case. |
04What this service doesn't do