Email Mailbox Checker - Verify Email Validity & Deliverability
Check if an email address is valid, verify domain existence, MX records, and SMTP connectivity. Get confidence levels to determine email deliverability.
Verify email address validity, check domain existence, MX records, and SMTP connectivity. Get confidence levels to determine if an email is safe to send to.
How It Works
This tool performs multiple checks to validate an email address and determine its deliverability.
- Validates email syntax using PHP filter_var
- Checks if the domain exists via DNS lookup
- Verifies MX (Mail Exchange) records are present
- Attempts SMTP handshake to verify mailbox (when possible)
Important Notes
- SMTP verification may not work for all providers (Gmail, Outlook, etc. often block unknown IPs)
- Some domains use catch-all addresses that accept all emails but bounce later
- Results are confidence levels, not absolute guarantees of deliverability
- Modern email providers may accept RCPT TO but bounce messages later
Frequently Asked Questions
This tool performs four levels of verification: email syntax validation, domain existence check via DNS lookup, MX (Mail Exchange) records verification to confirm the domain can receive email, and SMTP handshake attempt to verify the mailbox exists. Each check contributes to an overall confidence level.
No email validation can be 100% accurate. Some email providers (Gmail, Outlook, etc.) block verification attempts from unknown IPs, and some domains use catch-all addresses that accept all emails but bounce later. The results represent confidence levels, not absolute guarantees of deliverability.
Yes, you can check up to 50 email addresses at once. Enter them one per line or separated by commas. The tool will validate each address individually and provide separate results with confidence levels for each one.
