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Email Address Validator

Check one address or a whole list for format problems, with a per-address reason and a suggested fix for common domain typos.

One address per line, or separated by commas or semicolons. Results update live and nothing leaves your browser.

Results

Paste one address or a whole list to check it.

Copies every address whose format passed, duplicates removed. This checks the format of an address only. It cannot confirm that a mailbox exists, because that would mean contacting the mail server for the domain.

How to validate an email address

  1. Paste your addresses

    Enter one address or a whole list, separated by line breaks, commas, or semicolons.

  2. Read the verdicts

    Each address gets a valid, check, or invalid status with the exact reason, plus counts across the whole list.

  3. Fix the flagged ones

    Addresses with a likely domain typo show the corrected spelling, so you can repair them in place.

  4. Copy the clean list

    Copy every address whose format passed, with duplicates removed and the original order kept.

Why use this tool

Per-address reasons

Instead of a single pass or fail, every address is listed with the specific problem: no @ sign, a missing top-level domain, a stray character, or a length over the limit.

Typo detection with suggestions

Near misses on common mailbox providers, such as gmial.com, gmai.com, hotmial.com, yahooo.com, and outlok.com, are flagged with the corrected address.

Real length limits

The part before the @ is capped at 64 characters and the whole address at 254, which is where a lot of generated addresses quietly fail.

Bulk lists

Paste thousands of addresses at once. Duplicates are marked, role addresses like info@ and noreply@ are called out, and the counts update live.

One-click clean list

Copy only the addresses whose format passed, deduplicated and in the order you pasted them, ready to drop into a form or a script.

Runs entirely in your browser

Contact lists are private. Everything is checked on your device and no address is uploaded, stored, or logged.

About this tool

This tool checks whether an email address is written correctly. It reads one address or a whole pasted list and gives each one a verdict with a reason: a missing or duplicated @ sign, nothing before the @, a domain with no top-level part, a leading or trailing dot, two dots in a row, a hyphen at the edge of a domain label, characters that are not allowed, or a length over the 64 character limit for the part before the @ or the 254 character limit for the whole address.

Beyond the strict checks it looks for the mistakes people actually make. A domain a character or two away from a common mailbox provider is flagged with the correction, so gmial.com, gmai.com, hotmial.com, yahooo.com, and outlok.com all get a suggested fix rather than a silent pass. Duplicates are marked so a list can be deduplicated on the way out. Role addresses such as info@, support@, and noreply@ are called out separately, since they are usually a shared inbox rather than a person, and the display name form copied out of a mail client is understood so a pasted list works without cleanup first.

One honest limitation is worth stating plainly: this checks the format of an address and nothing more. It cannot confirm that a mailbox exists or that mail sent to it will arrive, because answering that would mean contacting the mail server that handles the domain, which no in-browser tool can do. Treat a valid verdict as "this is well formed", not "this person is reachable". Everything runs on your device, which matters for a contact list. To pull addresses out of a block of text first, use extract emails, and to tidy stray spacing or blank lines in a pasted list, remove empty lines and remove duplicate lines handle it.

Frequently asked questions

Does this confirm that an email address really exists?
No, and no in-browser tool can. Confirming a mailbox means contacting the mail server that handles the domain and asking about it, which requires a server-side connection. This tool checks the format of the address: whether it is written in a way a mail system will accept.
What does the check status mean?
Check means the format is fine but something looks off. That covers a domain that is one or two characters away from a common mailbox provider, a duplicate of an earlier entry, a role address such as info@ or noreply@, and the rarely supported forms like a quoted name before the @ or an address literal domain.
Which typos does it catch?
Near misses on widely used mailbox providers, both from a list of known misspellings such as gmial.com and hotmial.com and by comparing the domain against the common providers for a one or two character difference. Common top-level domain slips like .con, .cmo, and .ogr are corrected too.
Can I check a whole list at once?
Yes. Paste addresses separated by line breaks, commas, or semicolons and each one gets its own row. Up to 5,000 addresses are checked at a time, with a note when a longer list is cut off.
Which addresses does the copy button include?
Every address whose format passed, which means both the valid ones and the ones marked check, with duplicates removed and the original order kept. Anything marked invalid is left out.
Is my list uploaded anywhere?
No. Validation runs entirely in your browser. The addresses never leave your device, are never sent to a server, and are not stored or logged.

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