A small team, obsessed with getting the answer right.
We build email verification that actually resolves Gmail and Yahoo — the domains every other tool quietly gives up on. Here's what drives us.
Who we are
A focused engineering team building one thing well: an email verifier and finder that tells you the truth about an address — even on catch-all-protected Gmail and Yahoo domains. No bloat, no upsell maze, no paywalled accuracy.
What drives us
Deliverability shouldn't be a luxury. We want any sender — solo founder to agency — to protect their reputation without gambling on guesswork. So we made the honest choice the default: you only pay for answers you can act on.
We were tired of verifiers that give up.
SF Email Verifier started as a side project — we kept feeding the same lists into different commercial verifiers and getting wildly different answers. The thing that broke every tool the same way was Microsoft and Google. Real Yahoo mailboxes came back catch-all. Fake ones came back valid.
So we built something that doesn't do that. Provider-aware checks for Gmail and Yahoo, honest statuses for everything else, and a free tier that resets every day instead of expiring in a week. We don't charge for unknown results because charging for “we don't know” never sat right with us.
One verifier, one finder, one API — the same engine behind all three. If you find something we got wrong, please tell us. We read every message.
How we got here.
The problem
Same lists, different verifiers, wildly different answers — always breaking on Gmail and Yahoo.
Provider-aware engine
We built deeper, provider-specific checks so real mailboxes resolve valid and fakes resolve invalid.
Finder + API
Added an email finder by name and a REST API — the same engine, wherever you need it.
Free, forever
Launched 20 credits a day that reset daily, with unknown results always free. No trial clock.
What we care about.
Honesty by default
If we can't confirm an address, we say so — and we don't charge you for it.
Accuracy over easy
We do the hard provider-specific work instead of rubber-stamping catch-all domains.
Generous free tier
20 checks a day, forever. Real value before you ever think about paying.
Your data stays yours
Encrypted, auto-deleted in 7 days, never sold, shared, or used to train models.
Fast, then thorough
Single checks in under a second; tricky domains get the deeper pass they need.
Ship, listen, improve
We read every message and keep sharpening the engine on the cases that matter.
Try the engine yourself.
20 free credits every day, forever. No credit card, no trial clock.