Email Address Validator & Checker
Validate email syntax and verify if the receiving mail server actually exists.
Enter any email address into the box to instantly verify if it is structurally valid and technically capable of receiving mail. This tool is perfect for cleaning up your newsletter subscriber lists, verifying user registrations, or checking if a business contact's email is still active.
Rather than just performing a simple regex check, our validator goes a step further by reaching out to the global DNS hierarchy to verify that the domain name attached to the email actually possesses valid Mail Exchanger (MX) records.
How it works
Validating an email address properly is a multi-step process that requires both syntactic analysis and network verification.
Step 1: Syntax Validation. The tool first checks the email against the strict RFC 822 and RFC 5322 standards using PHP's native filtering engine. It ensures there are no illegal characters, guarantees the presence of exactly one @ symbol, and verifies that the local part (before the @) and the domain part (after the @) do not exceed their strict maximum character limits.
Step 2: Domain Verification. Even if an email is perfectly formatted (e.g., [email protected]), it is useless if the domain is dead. The tool extracts the domain and performs a live DNS query to check for active A records or MX records. If the domain has expired or the mail servers have been shut down, the tool will immediately flag the email as undeliverable.
Privacy Guarantee: We do NOT actually send an email to the user, and we do NOT store the email address you test. All checks are performed completely passively via DNS.
Frequently asked questions
Does this tool send a test email to the address?
No. We perform a passive validation check. We verify the mathematical syntax of the address and we query the public DNS records of the domain. We never send an actual email to the recipient, meaning they will not know you checked their address.
Can this tool verify if the specific inbox exists (e.g. [email protected])?
No. While some tools attempt an SMTP handshake (often called "pinging" the inbox), this practice is highly unreliable today. Modern email providers (like Gmail and Microsoft 365) actively block "inbox verification" attempts to protect user privacy and prevent spammers from harvesting active addresses. We strictly verify the syntax and the domain's MX records.
What is an MX record?
MX (Mail Exchanger) records are DNS instructions that tell the internet exactly which servers are responsible for accepting email on behalf of a specific domain name. If a domain has no MX records, it is technically impossible for it to receive an email.
Is this safe to use for sensitive client emails?
Absolutely. The email address is processed entirely in RAM during your web request and immediately discarded. Nothing is written to a database or shared with third parties.
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