Clean Data Before Analysis

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

No login required

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.

Enter

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Process

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

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✓Completely free — no hidden costs, ever

✓No account, email, or login required

✓Files never leave your device

✓No file size limits whatsoever

✓No watermarks on any output

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