Bulk email checker
Paste a list or upload a CSV and check up to 100 addresses at once: format, whether each domain receives mail, throwaway and role addresses, and typos like gmial.com. Download the result as CSV.
How to read the result
Valid: the format is right, the domain has working mail servers, and nothing marks the address as throwaway or mistyped. Risky: it may deliver, but it is a disposable domain, a likely typo, or a domain without proper MX records. Role addresses like info@ stay valid and carry a flag. Invalid: mail to it cannot be delivered. Could not check: the domain's DNS did not answer; try those again later rather than deleting them.
Before an import, drop the invalid rows, fix the typos the table suggests, and keep an eye on the risky ones after the first send. A valid result does not prove a mailbox exists, so bounces still need handling.
One address with the full explanation: email verifier. Checking the domain you send from: domain health check.
Questions
- Why only 100 addresses?
- It is a free tool for checking a sign-up export or a list before an import, not a list-cleaning service. 100 per check, a few checks an hour, keeps it fast for everyone and useless for scrubbing bought lists, which you should not mail anyway.
- Does it check that each mailbox exists?
- No. That needs a connection to every domain's mail server, which servers treat as address harvesting and which Gmail, Outlook and others answer falsely anyway. Each address gets every check that can be done without it. The only certain test is a real send with bounce handling.
- What happens to my file?
- The file is read in your browser; only the email addresses are sent, the other columns never leave your computer. The addresses are checked and the result comes back. Nothing is kept in memory, written to disk or logged, and the list is not put in the page address.
- What does the CSV export contain?
- One row per address: the address, the result (valid, risky, invalid or could not check), short flags such as disposable or likely typo, the suggested correction, the mailbox provider and one sentence on why. Filter the table first to export only the invalid or risky rows.
More free tools
No sign-up, nothing stored. All tools.
Domain email health check
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DMARC checker
Reads the DMARC policy, report addresses and alignment, and says what the policy actually does to spoofed mail.
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Blocklist checker
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Email address verifier
Format, mail servers, throwaway domains, role addresses and typos for one address.
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Whether an address or domain belongs to a throwaway-mail service.
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Paste email HTML, see it on desktop and phone with images on or off, and what breaks in Gmail and Outlook.
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