Dedupe Email Lists

Clean up email lists before importing into Mailchimp, SendGrid, or other ESPs.

Geen aanmelding vereist

Ignore caseTrim whitespaceIgnore empty lines

Input (one item per line)

Occurrence counts

Output will appear here…

Email Lists tips

📧

Most ESPs charge per subscriber and reject duplicates anyway. Dedupe before importing to save credits and prevent errors.

💡

Enable "Ignore case" — Alice@Example.com and alice@example.com are the same address.

🎯

Use "Count occurrences" mode first to see if you have a few duplicates or thousands — gauges the data quality.

Invoer

Enter your data into the tool above. Everything stays local to your browser.

Verwerken

The tool processes your data instantly in your browser using JavaScript. No server, no waiting.

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Get your result instantly. Nothing is stored after you leave the page — complete privacy.

✓Volledig gratis — geen verborgen kosten, ooit

✓Geen account, e-mail of aanmelding vereist

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✓Geen watermerken op uitvoer

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Paste a list of words/keywords to see which appear

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