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Large CSV Splitter
Split huge CSV files by rows, file size, equal parts or column value, reading in pieces so even 1 GB files work.
Free, no uploads, no sign-up. Runs 100% in your browser.
How Large CSV Splitter works
Files are opened in your browser with SheetJS and JSZip. Nothing is uploaded, and your original file is never changed. The file is streamed 4 MB at a time, and quoted fields that contain line breaks stay together. The header is copied to every part.
Input: CSV, TSV, TXT. Output: ZIP, CSV.
How to use Large CSV Splitter
- Drop a CSV.
- Pick rows, size, parts or column value.
- Press Split file and download the ZIP.
Tips
- Excel, ODS and CSV all work. Formulas are read as their last saved values.
- For CSV files with odd characters, save them as UTF-8 first.
Large CSV Splitter FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
Related tools
- Split Excel Workbook: Save each sheet as its own file, cut a long sheet every N rows, or split rows by the value in a column.
- CSV & Spreadsheet Editor: Edit CSV and Excel files in a fast grid: sort, filter, dedupe, find and replace, split and merge.
- Merge Excel Files: Combine sheets from many Excel, ODS or CSV files into one workbook, or stack their rows into one table.
- Remove Duplicate Rows: Delete repeated rows from Excel or CSV, matching on all columns or the ones you pick, ignoring case and spaces.