Email verifier
An email checker that doesn't give up on Gmail and Yahoo.
Verify a single address in real time or clean a whole list in bulk. 20 free credits every day, and you only pay for results you can actually act on.
Try a Gmail or Yahoo address — that's where most verifiers quietly fail.
> awaiting input…
> runs 8 checks: syntax, mx, smtp, catch-all, role, disposable, free-provider, spam-trap
> typical response: 800–1500ms
How verification works
Four checks, one credit, an answer you can trust.
Confirms the address is well-formed and that the domain has a working mail server before spending a credit.
Connects to the real mail server and asks whether the specific mailbox accepts mail — the same step most checkers stop at.
For Gmail and Yahoo/Microsoft domains, runs deeper checks instead of defaulting to a generic catch-all label.
Flags throwaway domains and generic addresses like info@ or support@ so you can decide how to treat them.
Why this matters
Catch-all domains break basic SMTP checks.
A mail server can return the same accept signal for a real mailbox and a made-up one — that's true on any catch-all domain, but it's especially common on Microsoft/Yahoo tenants and Gmail Workspace setups. A verifier that doesn't account for this either rubber-stamps junk as valid or discards real contacts as catch-all.
What we do differently
- Provider-aware logic for Gmail and Yahoo instead of one generic SMTP probe
- Clear status per address: valid, invalid, risky, or disposable — never a vague “unknown” dump
- Unknown and greylisted results are free, so ambiguity never costs you a credit
Bulk email verifier
Clean a list of 10 or 100,000 the same way.
- CSV or TXT, up to 1M rows per job
- Jobs auto-delete after 7 days for privacy
- Only actionable results use a credit
email,status jane@Yahoo.com,valid sales@bigco.com,valid asdkj923@mailinator.com,disposable typo@gmali.com,invalid
Verification API
Verify at signup, not after the bounce.
Call the same engine behind the dashboard from your own signup form, CRM, or outreach tool. JSON in, a clear status out.
curl https://api.sfemailverifier.com/v1/verify \ -H "Authorization: Bearer YOUR_KEY" \ -d email=jane@Yahoo.com
{
"email": "jane@Yahoo.com",
"status": "valid",
"disposable": false,
"credit_used": true
}Email verifier FAQ
What's the difference between an email checker and an email validator?+
People use the terms interchangeably. We run both layers: syntax/format validation (does it look like a real address) and live deliverability verification (does the mailbox actually exist and accept mail).
Do unknown or catch-all results cost a credit?+
Unknown and greylisted results are always free. Catch-all results cost a credit because they're actionable — many businesses choose to send to catch-all domains anyway.
Can I verify a list in bulk?+
Yes — upload a CSV with up to 1M rows. We process in the background and you get a result CSV you can download. Per-row cost is the same as single checks.
Is there a verification API?+
Yes. Every plan, including the free 20-credit daily tier, includes the same JSON API the dashboard uses. Bearer-token auth, JSON responses.
Start verifying for free, right now.
20 credits every day, forever. No credit card, no trial clock.