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Runs in your browserCSV tools
Split, merge, clean and convert CSV files. The ones that are too big to open, land in a single column, or get rejected on import.
- Split CSV
Break a big CSV into numbered parts, each keeping the header row.
- Merge CSV
Merge several CSVs into one file, with one header row.
- Remove duplicate rows
Remove duplicate rows, matching on the whole row or one column.
- CSV to JSON
Turn a CSV into JSON, one object per row.
- JSON to CSV
Turn JSON into a CSV that opens in Excel.
- Change CSV delimiter
Swap commas for semicolons or back, so Excel stops putting it all in column A.
- Sort CSV
Sort by any column, as text or numbers, with whole rows moving together.
- Filter CSV rows
Pull out the active customers, or drop the test rows.
- Select CSV columns
Keep the 4 columns you need from a 40-column export, or remove the ones you don't.
- CSV to Markdown table
Turn a CSV into a Markdown table for a README or docs.
- Compare CSV files
See what changed between last month's export and this month's.
Nothing here is uploaded
These tools are ordinary web pages that happen to contain the whole program. When you choose a file, your browser reads it from your disk into its own memory and the work happens there. There is no upload step, because there is nowhere for it to go — the site is static files with no backend.
That has a practical consequence beyond privacy: there are no queues, no file size caps set by someone else's bandwidth bill, and no daily limits designed to sell you an upgrade. How this works →