1 in 5 web form submissions contains a fake or mistyped email. Check any address in real time - no account needed.
Checks syntax - MX records - SMTP mailbox - catch-all behavior - disposable detection
Invalid emails hurt your sender reputation, waste ad spend, and corrupt your CRM. Checking first costs nothing.
Typos, disposable addresses, and fake emails account for 1 in 5 web form submissions on average.
Most email service providers flag campaigns with over 2% hard bounces, risking account suspension.
Job changes, company closures, and domain reconfigurations make enterprise email lists decay fast.
One bad campaign to an unvalidated list can cost more to recover from than years of checking would have.
Five verification stages run in sequence, each adding a layer of confidence to the final verdict.
RFC 5321 format check, invalid characters, role address detection (admin@, noreply@).
DNS resolution, MX record lookup, mail server fingerprinting, SPF/DMARC analysis.
Live RCPT TO handshake with the mail server. Confirms the mailbox exists without sending a message.
3-probe test using random addresses flags domains that accept everything - protecting you from false positives.
XGBoost + Bayesian models score deliverability probability when SMTP probes are blocked by the provider.
Verify a prospect's email before your first contact. A hard bounce on a cold email burns your domain reputation permanently.
Check new contacts from sign-up forms, event registrations, or contact pages before adding them to your CRM or campaign list.
Diagnose a specific bounce - is the mailbox gone, the domain down, or the server blocking you? The checker tells you why.
Confirm your company or personal email is reachable before sharing it on a website, resume, or business card.
The single-address checker is ideal for spot checks. To clean an entire list, upload a CSV and get results in minutes - 2,000 verified addresses for $6, no subscription and no monthly minimum.
Start with 100 free credits - no card required. See pricing
New to verification? Start with the complete email verification guide.
An email checker verifies whether an email address is real, correctly formatted, and able to receive messages. It goes beyond a simple syntax check by connecting to the actual mail server and confirming the mailbox exists - without sending a test email.
Type or paste the email into the checker above and click Check Email. BounceZero runs a 5-stage pipeline - syntax, MX records, SMTP handshake, catch-all probe, and ML scoring - and returns a verdict within seconds.
For most providers, yes. BounceZero's SMTP check contacts the mail server and tests whether the mailbox accepts messages. Dormant Yahoo accounts, deactivated corporate mailboxes, and deleted Gmail accounts all return different SMTP signals that our engine interprets to give you a deliverability verdict.
97-99% accuracy on Outlook, Yahoo, corporate, and ISP domains where SMTP probing is permitted. Gmail suppresses SMTP responses, so Gmail checks rely on our ML model (trained on millions of outcomes). Catch-all domains are probed individually against the provider to resolve them; any that stay unresolved are flagged as catch-all.
You get 3 free email checks per session without an account. Sign up for a free BounceZero account to get 100 checks per month - no credit card required, and unused credits never expire.
Every invalid address you send to costs you sender reputation. Clean your list with 100 free credits - no card needed.
Single-email checks, no signup required
Verify a single address instantly
Verify a whole list up to your free monthly credits
Validate email before you send
See exactly what an MX server says
Find which domains accept anything
Spot 10minutemail-class temp addresses
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