Upload or paste your CSV
Paste your CSV data or upload a file. The first row should contain your column headers.
CSV Deduplicator
Remove duplicate rows from a CSV instantly in your browser. Paste CSV data or upload a file, choose how to deduplicate it, and get a clean CSV in seconds. Fast, free, and private.
Or upload a CSV file
In your browser · Up to 200 MB (50+ MB may feel slow)
Header row
Duplicate handling
Columns to use as the deduplication key
Column names will appear here after CSV is loaded.
Results
Files are processed entirely in your browser and are never uploaded to any server.
How it works
How to remove duplicates from a CSV
Upload your CSV, choose how to identify duplicate rows, and download a deduplicated file. Everything runs in your browser with no uploads or data leaving your device.
Choose how to identify duplicates
Select whether to remove exact duplicate rows or match duplicates based on specific columns.
Download the deduplicated CSV
Remove duplicates and download the cleaned file instantly, or copy it to your clipboard.
Why use this tool
Why Use a CSV Deduplicator?
Removing duplicate rows keeps your data clean and easier to work with. A CSV deduplicator helps you prepare exports for import, strip repeated records, and avoid errors from duplicate entries.
Clean exports before import
Remove repeated records so databases and tools receive unique rows only.
Prepare data for Excel or Sheets
Deduplicate before opening in spreadsheets or feeding into scripts.
Reduce errors from duplicates
Avoid double-counting or conflicting rows in analysis and imports.
Keep datasets smaller
Smaller, duplicate-free files are easier to share and process.
Privacy
Private and Secure CSV Deduplication
Your files and pasted data are never uploaded to a server. This CSV deduplicator runs entirely in your browser using client-side processing.
Data stays on your device
Your data never leaves your browser. No uploads, no cloud storage, no logs.
Nothing stored or sent
No files are stored or transmitted. Deduplication happens only in memory.
Fast and private
Deduplication is instant and runs locally at full browser speed.
FAQ
Frequently asked questions
Paste or upload your CSV, choose “Entire row” for exact duplicates or “Selected columns” to match on specific columns, set header option if needed, then run. The first occurrence is kept; later duplicates are removed. Download the result.
Yes. Deduplication runs in your browser. The output is standard CSV and works in Excel, Google Sheets, and other tools.
If you check “This file has a header row,” the first row is always kept and is not used when finding duplicates.
Yes. Processing runs locally in your browser. Nothing is uploaded or stored.
Yes. Choose “Duplicate values in selected columns” and select that column. Rows with the same value in it are treated as duplicates; the first is kept.
The parser handles quoted fields correctly. Values with commas, quotes, or newlines are read as single cells, and the output re-escapes them so the CSV stays valid.