Split CSV Files Online
How do you split a CSV file? Drop your file below, choose to split by rows, file size or column value, and click Split. Each part keeps the header row and downloads instantly. Free, no signup, and your file never leaves your device.
Drop your CSV file here or click to browse
Processed locally — never uploaded
How to split a CSV file (step by step)
- Add your file. Drag and drop the CSV into the box above, or click it to browse. A preview of the first rows appears instantly.
- Pick a split mode. By rows (e.g. 1,000 rows per file), by file size (e.g. 5 MB parts) or by column value (one file per unique value in a column).
- Click "Split CSV". A live counter shows rows processed. Large files stay responsive thanks to streaming in a background worker.
- Download the parts. Save files individually or click "Download all as ZIP".
Why use this CSV splitter?
- Private by design: files are processed on your device, never uploaded to a server.
- No limits, no signup: split unlimited files of any size, completely free.
- Headers preserved: every part is a valid, self-contained CSV.
- Three split modes: by rows, by file size, or by unique column values.
- Fast on large files: streaming processing handles hundreds of megabytes without freezing your browser.
Frequently asked questions
How do I split a large CSV file?
Drop your file into the tool above, choose how to split it (by rows, file size or column value) and click Split. Each part downloads as a separate CSV, or grab them all in one ZIP. Everything runs in your browser, so even very large files split in seconds.
Does each split file keep the header row?
Yes. Leave "First row is a header" checked and every output file starts with the original header row, so each part opens cleanly in Excel or imports into any database.
Can I split a CSV by the values in a column?
Yes. Choose "By column value" mode and pick a column. The tool creates one file per unique value, for example one file per country, region or category.
What is the maximum file size?
There is no fixed limit. The file is processed as a stream in a background worker, so files of several hundred megabytes work on a normal laptop without freezing the page.
Is my data uploaded anywhere?
No. The splitter runs 100% in your browser. Your file never leaves your device, which makes it safe for confidential data.
How do I split a CSV so Excel can open it?
Excel supports at most 1,048,576 rows per sheet. Split by rows with a value of 1,000,000 or less and every part will open in Excel without truncation.