Rapid Email Validator
Catch bad syntax, dead domains, and disposable addresses — without storing your data.
Privacy-first, free, open-source email validation. Syntax, DNS/MX, disposable and role checks. VALID means the domain can receive mail, not that a specific inbox exists.
What this validates
VALID means the address is syntactically OK and the domain can receive mail. It does not mean a specific inbox exists.
We check
- Syntax
- DNS and MX records (the provider can accept mail)
- Known disposable domains
- Role addresses (info@, admin@, and similar)
- Alias normalization for major providers
- Typo suggestions
- A derived score and status
We don't check
- SMTP RCPT TO
- Whether a specific mailbox or inbox exists
- Catch-all domains
- Whether a message will bounce
mailbox_exists is true when the email provider (domain MX) can accept mail. It matches mx_records and does not prove the local-part mailbox exists.
Why we don't check SMTP
SMTP RCPT TO asks a mail server if it will accept one address. That reply does not prove the mailbox exists. Major providers hide whether the inbox is real, catch-all domains accept every address, and many servers block or throttle automated checks. It is also too slow: each address needs its own live connection to a mail server. A yes would look like inbox verification and still be wrong, so this API never sends one.
Why we can't know if an email exists
No check can say with certainty that a specific mailbox exists. Syntax only says the address is well formed. DNS and MX only say the domain can accept mail, not that this local-part is real. There is no public directory of inboxes. Even SMTP cannot settle it, because providers hide existence and catch-all domains accept every address. An address can pass every check here and still not be a real inbox. The reliable confirmation is double opt-in: the person clicks a link you send.
🛡️ Privacy First
Zero data storage - your emails are never saved! GDPR, CCPA, and PIPEDA compliant
💎 Free & Open
No account and no usage limits. Syntax, DNS/MX, disposable and role checks, in the open.
⚡ Lightning Fast
Quick response times to keep your apps snappy
🎳 Batch Ready
Validate up to 100 emails at once
🗑️ Disposable Detection
Flags addresses on a maintained list of known disposable domains
📨 Domain & MX
Confirms the provider or domain can accept mail. Does not prove a specific inbox exists.
Everything You Need, Completely Free
- Unlimited email validations
- No credit card required
- No usage limits
- MIT open source
- Disposable email detection
- Domain and MX checks
- Alias detection
- Typo suggestions
- Batch validation
- Role detection
- No data storage
- No tracking
- GDPR, CCPA, and PIPEDA compliant
- Quick integration
- Clear documentation
- Simple REST API
- Maintained disposable-domain list
Start Validating Emails Now
Enter an email address and click validate to see it in action
Why Is This Free & Open Source?
As a fellow developer, I understand the challenges solopreneurs and small teams face. Not everyone can afford expensive email validation services, yet everyone deserves access to reliable tools. This service is my contribution to the developer community - completely free and open source, with no strings attached. Use it respectfully, and if you find it valuable, consider supporting the project with a coffee! ☕
🤝 Community First
Built by developers, for developers. Open source, no corporate interests, just genuine community support.
🔒 Privacy Focused
We never store your email addresses. Your data is processed in memory and immediately discarded.
💝 Support If You Can
This service runs on love for the community and coffee. Buy me a coffee if you find it useful!
API Documentation
No authentication required. Validation covers syntax, DNS/MX, disposable and role checks. mailbox_exists means the provider can accept mail, not that a specific inbox exists.
Feedback Welcome! 🙌
Your feedback helps make this tool better for everyone in the community.