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Email list de-duplicator.

Paste a list of email addresses and strip out the duplicates in seconds. Case is ignored, so Jane@… and jane@… collapse to one, and anything without an @ is skipped. It all runs right here in your browser - nothing is uploaded.

Runs entirely in your browser - nothing is uploaded.

Why de-duplicate before you send

Duplicate addresses creep in whenever lists get merged, exported, and re-imported. Left in place they inflate your counts, waste sending credits, and risk mailing the same person twice from one campaign. Removing exact repeats is the quickest, safest first pass of cleaning an email list - it's lossless (you only drop true copies) and needs no judgment calls, so it's the right thing to do before any heavier hygiene.

Case-insensitive matching
Addresses are compared in lowercase, so mixed-case duplicates are caught - the first spelling you pasted is the one that's kept.
Order preserved
The cleaned list stays in the order you pasted it, minus the repeats - nothing is re-sorted or rewritten behind your back.

De-duplication is a first step, not verification

Removing duplicates makes a list tidier, but it says nothing about whether the remaining addresses can actually receive mail. A unique address can still be a typo, a long-dead mailbox, or a disposable inbox that will hard-bounce. That's the job of bulk email verification, which checks each address against DNS and the mailbox itself and returns a confidence score. Deduplicate first to cut the volume, then verify what's left so you only send to addresses that resolve.

Email list de-duplicator FAQ

It takes a pasted list of email addresses, trims each one, ignores case when comparing, and removes exact duplicates - keeping the first occurrence in the order you pasted it. It also skips any token that has no '@' as clearly-not-an-email, and shows you how many were pasted, kept, removed as duplicates, and skipped. You get a clean list you can copy or download as a .txt file.

Nothing leaves your browser. The whole process (splitting, trimming, comparing and de-duplicating) runs locally in JavaScript on your device. There's no API call, no server round-trip, and no logging of your list. You can even disconnect from the network and it still works.

No. De-duplication is not validation: this tool only removes repeats and obvious non-emails, and it never confirms that a mailbox exists or can receive mail. A deduped list can still be full of dead or mistyped addresses. To find those, pair it with the full email verifier, which runs syntax, DNS, disposable, role, catch-all and SMTP checks and scores each address.

One address per line works, and so does a single line or block separated by commas, semicolons, spaces or tabs - any mix of those. It splits on all of them at once, so you can paste straight from a spreadsheet column, a CSV cell, or a comma-separated string without reformatting first.

Verify the deduped list

Once the duplicates are gone, run the unique addresses through full verification to remove the dead ones too - start free with 100 credits, no card required.

Start verifying