Launching today

skink
Email verification API with calibrated confidence
2 followers
Email verification API with calibrated confidence
2 followers
Real-time email verification API — actual SMTP handshakes, not just syntax checks. Resolves catch-alls, even behind Proofpoint/Mimecast, where most tools return "unknown." Every result ships reasons[] and a calibrated confidence score, never laundered into a false "deliverable." MCP server for Claude/Cursor, or bulk CSV. Unknown results are free. We verify your list and stop there — encrypted at rest, retention you set. 100 free credits, no card.










Hey PH! I'm Sagar, and I built skink.
Here's the problem in plain terms: when you check whether an email address is real, tools normally give you one of three answers — yes, no, or "I don't know." That third answer happens a lot: roughly 1 in 7 business email addresses sit on catch-all domains, which is where most of the "I don't know"s come from. Most tools just shrug — and charge you for the shrug.
skink tries to actually answer the "I don't know" case instead of giving up on it. When it can't be fully sure, it tells you why — and how sure — instead of a vague error. And unknown results are always free: you only pay for answers.
Free to try — no signup, no card, right in the browser. Or grab an API key: 100 free credits, never expire.
Who it's for: developers, outbound/sales teams, CRM hygiene, newsletter operators — anyone whose sender reputation depends on list quality.
For the technical folks: the "I don't know" case is catch-all domains and SEG-protected inboxes (Proofpoint, Mimecast, Barracuda). Legacy verifiers either give up or proxy-hop to force a fake answer. skink resolves them out-of-band with a calibrated confidence score, re-checked nightly against real delivery outcomes, plus reasons[] on every result instead of just a status code. 0% false-confirms on fake mailboxes in our own controlled ground-truth test — methodology at skink.dev/accuracy.
Privacy is architecture, not policy: hashed by default, purged in 7 days, never sold.
Would genuinely love feedback — especially from anyone who's been burned by a verifier lying to them about a catch-all address.