Clean Data Before Analysis

Find duplicate rows in CSV exports or database dumps before analytics work.

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Ignore caseTrim whitespaceIgnore empty lines

Input (one item per line)

Occurrence counts

Output will appear here…

Data Cleanup tips

🧹

For customer data deduplication, paste a column (e.g. emails or phone numbers) — find collisions before running joins.

💡

For log file analysis, the "Count occurrences" mode quickly tells you the most-frequent log entries.

🎯

For database row deduplication, export to a single-column list, find duplicates, then craft a DELETE query for them.

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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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Dedupe Email Lists

Clean up email lists before importing into Mailchi

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