CSV Diff
Compare two CSV files and highlight added, removed, and changed rows. Securely process files in your browser memory with zero
Your files never leave your device. Processed locally. 100% private.
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How To Use CSV Diff
Complete your task perfectly in just three straightforward steps.
Upload two CSVs
Upload the original and the updated CSV.
Choose key column
Select a unique identifier column to match rows.
Download diff report
Download a diff showing added, removed, and changed rows.
FAQ
Everything you need to know about the CSV Diff.
How are rows matched?
By a key column you choose: ID, email, order number, etc.
What if there is no unique key?
Use row-order matching to compare position by position.
Is my file uploaded?
No. Everything runs locally in your browser.
File size limit?
Process files up to the browser memory limit.
Can I export only changed rows?
Yes — filter the diff to additions, deletions, or modifications only.
How are modified rows detected?
The tool matches rows from File A and File B using the primary key column you select. For each matched pair, it compares every cell value. If any cell differs, the row is classified as modified and the changed column names are listed. The original and new values are shown side by side so you can see exactly what changed.
What if the two CSVs have different columns?
The diff still runs. Columns present in one file but not the other are included in the result with empty values for the file that lacks them. The summary shows the total counts of added rows, removed rows, and modified rows, giving you a full picture of what changed between the two versions.
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