Dedupe Email Lists

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

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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.

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

Proses

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.

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Clean Data Before Analysis

Find duplicate rows in CSV exports or database dum

Identify Repeats in To-Do Lists

Spot duplicate tasks in long to-do lists or projec

Count Word Frequency

Paste a list of words/keywords to see which appear

Find Repeated Commit Messages

Paste a git log to find authors' habitual commit m