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CSV Compare
Analyze two CSV tables side by side, spot additions, removals, or changes, and get a clear report of the differences.
- 100% local
- Instant
- Free
- No account
- Works offline
- Clipboard
Data not sent
Data not sent
Use a name or 1-based column number. Leave empty to compare complete rows.
Comparison report
Details
Why use this tool?
Compare two CSV files and identify added, removed, changed, or unchanged rows using a selected comparison key.
Smart processing
Clean, structure, and transform your data with rules tailored to the format being processed.
Supported formats
CSV, XLSX, and other tabular formats depending on each tool’s capabilities.
Save time
Get a clean, ready-to-use result in seconds without installing software or configuring a complex workflow.
Fonctionnement
How does this tool work?
The tool compares both CSV files row by row using the selected key or every column. It highlights rows that were added, removed, or modified, preserves the original structure whenever possible, and generates a clear comparison report that is easy to review, export, and share with your team.
Use cases
Review two exports
Understand changes between two successive data extractions.
Verify a migration
Compare records before and after a transformation or transfer.
Audit synchronization
Find missing or changed records across two systems.
Guide
How to use this tool
- 1
Add the data
Paste the CSV or provide the information required by the tool.
- 2
Configure processing
Choose the columns, rules, or options that match your objective.
- 3
Review the result
Check the report, then copy or download the generated data.
Tips and best practices
- Keep a copy of the source file before applying an important transformation.
- Check the delimiter and header-row setting before running the operation.
- All processing stays in your browser and no CSV file is uploaded.
Frequently asked questions
Are my CSV data uploaded?
No. Parsing, comparisons, and transformations are executed locally in your browser.
Are quoted fields supported?
Yes. The CSV engine supports delimiters inside quoted fields and multiline quoted content.
Can I download the result?
Yes. When a new CSV is produced, it can be copied or downloaded directly from the page.
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