Enter any email address below and get a real-time deliverability verdict in seconds. No account needed.
Our 5-stage verification pipeline analyzes every email across 40+ signals — far beyond a simple format check.
RFC 5321 compliance, invalid characters, role-based detection (admin@, info@), disposable domain check.
DNS MX lookup, SPF/DKIM/DMARC analysis, domain age, mail server fingerprinting.
RCPT TO mailbox check, greylisting retry logic, 3-probe catch-all detection algorithm.
Gravatar presence, breach data correlation, spam trap pattern detection, provider heuristics.
Bayesian likelihood ratios blended with XGBoost and Random Forest models trained on millions of outcomes.
Every result comes with a classification, confidence score, and detailed signal breakdown.
The mailbox exists and will accept messages. Safe to send. Confidence score above 75.
The address may deliver but shows risk factors: catch-all domain, disposable provider, role address, or low reputation score.
The mailbox does not exist, the domain has no MX records, or the SMTP server rejected the address. Do not send.
The mail server blocked the SMTP probe or timed out. ML scoring provides a probability estimate based on available signals.
Verify a prospect or contact's email before reaching out to avoid hard bounces.
Check new contact details from business cards, LinkedIn, or web forms before adding them to your CRM.
Confirm your company or personal email address is configured correctly and MX records are live.
Understand why a specific address bounced — invalid mailbox, full inbox, blocked server, or catch-all domain.
The free verifier is great for individual checks. When you need to verify thousands of addresses at once, BounceZero's bulk upload lets you clean entire CSV lists in minutes.
Yes. You can verify individual email addresses using the demo tool above with no account required. For bulk verification or API access, sign up for a free account to receive 100 credits — no credit card needed.
SMTP verification opens a connection to the recipient mail server and issues a RCPT TO command to check if the mailbox exists — without sending an actual email. BounceZero goes further by running a 3-probe catch-all test to detect domains that accept all addresses regardless of whether the mailbox exists.
Yes. BounceZero runs three SMTP probes using randomized addresses to fingerprint catch-all behavior. If a domain accepts all addresses, we classify the result as Risky / Catch-All rather than Deliverable — protecting you from bulk sends that would bounce at delivery time.
BounceZero maintains behavioral profiles for 200+ mail providers including Gmail, Outlook/Hotmail, Yahoo, and corporate domains. For providers that block SMTP probes (like Gmail), we use domain intelligence, Gravatar lookups, and ML scoring to estimate deliverability with high confidence.
Absolutely. BounceZero stores only a hashed fingerprint of each verified address for caching purposes. We never sell or share email data with third parties and are fully GDPR compliant. You can request deletion of any stored data at any time.
Start for free with 100 credits. Upload a CSV, verify via API, or add real-time validation at your sign-up form.