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Runs in your browserCSV tools
Split, merge, clean and convert CSV files without sending your data anywhere. Spreadsheets full of customer records shouldn't be uploaded to a stranger's server.
- Split CSV
Break a big CSV into smaller files, header preserved on each.
- Merge CSV
Combine many CSVs into one, without repeated header rows.
- Remove duplicate rows
Deduplicate a CSV across all columns, or by one key column.
- CSV to JSON
Turn a CSV into a clean JSON array of objects.
- JSON to CSV
Turn a JSON array into a spreadsheet-ready CSV.
- Change CSV delimiter
Convert between comma, semicolon, tab and pipe delimiters.
- Sort CSV
Sort by any column, as text or numbers, either direction.
- Filter CSV rows
Keep or remove rows where a column matches a condition.
- Select CSV columns
Delete unwanted columns, or keep and reorder only the ones you name.
- CSV to Markdown table
Turn a CSV into a Markdown table, properly aligned and escaped.
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 →