Split a CSV file
Large CSVs get rejected everywhere — import limits, email attachment caps, spreadsheet row ceilings. This splits one file into numbered parts of whatever size you choose, and repeats the header row at the top of every part so each piece opens cleanly on its own.
Your file stays on this computer. There’s no upload button here, because there’s nowhere to send it. This tool runs inside the page you opened — like a calculator on a web page, it keeps working once it has loaded. How this works, and how to check it →
How to use it
- Choose your CSV file.
- Set how many rows each part should contain (the header row doesn't count towards this).
- Click Split, then download the parts individually or all together as a zip.
Questions
Is my file uploaded anywhere?
No. The whole tool is inside this page, so the work happens on your computer. There is no server to send it to. If you'd rather check than take our word for it: use the tool once, on a sample file, with the settings you want. Then turn off your wi-fi and do exactly the same thing again in that tab, without reloading. It still works, because everything it needs is already here.
Does each part keep the header row?
Yes, by default. Every part starts with the same header your original file had, so each one imports correctly on its own. You can turn this off if you plan to concatenate the parts again later.
How large a file can it handle?
Files up to a few hundred megabytes are normally fine on a modern laptop. The real limit is your computer's memory, because the file is held in this page rather than sent away. A very large file takes a while to load, but the split itself is quick.
What happens to commas inside quoted fields?
They're preserved. The file is parsed as proper CSV rather than split on raw commas, so quoted fields containing commas, line breaks or escaped quotes survive intact.