Free · Browser-local tools
Compare CSV files
Compare two CSV files by a unique key column. Review added, removed, and changed records, then download a CSV report.
Compare CSV
Compare two versions of your CSV
Open your file in the CSV editor with this tool already selected. Preview the result before downloading.
- Choose updated, then original CSV.
- Select a complete unique key column.
- Review added, removed and changed values, then download the full report.
Free · No signup · File contents stay in your browser. Back to page and Resume keep your edits in this tab. Download your edited copy before refreshing; refresh opens the original file. Open files up to 1 GiB with browser storage.
Try a small example
3 records · 3 columns| id | name | amount |
|---|---|---|
| 1 | Example one | 12 |
| 2 | Example two | 24 |
| 3 | Example three | 18 |
Example difference
Key id=2 · amount: 24 → 30
Illustrative fictional data. Open the sample to try the tool with an updated comparison file included.
How to compare csv
- 1
Choose updated, then original CSV.
- 2
Select a complete unique key column.
- 3
Review added, removed and changed values, then download the full report.
What to expect
Files need identical ordered headers and unique nonblank keys. Structured differences retain exact source values and column context; original tables remain intact.
Local files and clear limits
These tools process file contents on your device. The browser workspace accepts files up to 1 GiB and 5 million records, subject to available browser storage and decoded-record limits. This tool's calculations support up to 100,000 records, 2 million cells and 64 MB of text. Download a new copy to keep your result.
Plain answers
Compare CSV questions
What can I do with this compare csv tool?+
Files need identical ordered headers and unique nonblank keys. Structured differences retain exact source values and column context; original tables remain intact.
Does my CSV leave my device?+
File selection, editing and these task operations run in your browser. No account or file upload is required. Download a new copy to keep your result; refreshing restores the original input, not unsaved edits.
Do the editor and task have the same file limits?+
The editor opens files up to 1 GiB and 5 million records, subject to browser storage and decoded-record limits. This task supports up to 100,000 records, 2 million cells and 64 MB of decoded text.