Single check
Free email checker
Enter one address. Mail7 checks the syntax, the domain's mail servers and then the mailbox itself, and tells you which of the three answers it earned: Valid, Not Valid or Unknown.
Reading the answer
Three answers, and what each one is worth
- Valid
- The server confirmed the mailbox exists and accepts mail. Safe to send.
- Not Valid
- Broken syntax, no mail server, a disposable domain, or a mailbox the server says does not exist.
- Unknown
- No proof either way. Keep the address, watch how it behaves, and do not treat it as a bounce.
Background
Learn more about email checker
Email verification is the process of establishing whether an address can actually receive mail, without sending anything to it. Removing the addresses that provably do not exist keeps bounce rates down, protects your sender reputation, and stops you paying your email platform to deliver to nobody. What verification cannot do is prove who is behind an address, and no honest checker claims otherwise.
Different types of email verification methods
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Syntax validation: This checks the email address to ensure that it has a valid format and domain name.
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DNS validation: This looks up the domain name associated with the email address to confirm that it is a valid domain and that it has the proper MX records.
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Mailbox validation: This opens an SMTP conversation with the mail server and asks whether it would accept mail for that one address. The conversation is closed before any message is sent.
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Catch-all test: Some domains accept mail for every address, existing or not. We probe for that, because on such a domain an accepted address proves nothing - the honest answer there is Unknown, not Valid.
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Disposable check: Throwaway addresses from temporary-mail services are flagged. They often do receive mail, so they are not marked Not Valid - they are marked Unknown and tagged Disposable.
Important note
No verification method is foolproof, and this one is not either. Some mail servers deliberately hide whether a mailbox exists, others accept everything and drop the message later. That is exactly why a third answer exists here: when the server does not give us proof, you get Unknown rather than a guess dressed up as a verdict.
How our email checker works
Sent something and never got a reply? Check whether the address exists before you assume you were ignored.
The check runs in four stages. We read the syntax, look up the domain's MX records, connect to the mail server those records point at, and ask it about this one mailbox. Whatever the server answers becomes the verdict you see, quoted back to you in its own words.
How much the server is willing to say depends on how it is configured. Business domains and providers like Google usually answer plainly. Others - Microsoft and Yahoo among them - refuse to confirm or deny any mailbox, and a catch-all domain accepts every address regardless. In all of those cases we return Unknown, because the server gave us nothing to stand on.
Unknown is not a failed check and not a bad address. It means the evidence is missing, so the decision is yours: keep the address, send to it if the rest of your list is healthy, and watch how it behaves. If you want a second opinion, send one real message and check your own server's logs for a bounce a day later.
Note: this page is built for one address at a time. For a list, use the bulk email checker.
Questions
Frequently asked questions
How accurate is the email checker?
Our email checker uses multiple layers of validation: syntax checking, MX record verification, and a live SMTP connection to the mail server. For most common providers and business domains the results are highly reliable. However, no tool can verify every address with 100% certainty - some servers (catch-all domains, greylisting, and providers like Outlook/Microsoft or Yahoo) intentionally do not reveal whether a mailbox exists. In those cases we honestly return the status "Unknown" instead of guessing.
What does the email validation process include?
Our validation process includes three main steps: syntax checking to verify proper email format, MX records verification to confirm domain validity, and SMTP connection testing to ensure the mailbox exists.
How long does email validation take?
Email validation typically takes less than 2 seconds per email address. The process includes real-time checking of format, domain, and mailbox existence to provide accurate results quickly.
Is my email address safe when using this tool?
Yes, your email address is completely safe. We do not store, save, or share any email addresses you validate. All data is processed in real-time and immediately discarded for your privacy protection.