Split CSV Files — By Rows or By Column Value

What you get

In "Every N rows" mode the first file keeps the header and each part is named part-01.csv, part-02.csv… In "By column value" mode every distinct value in the chosen column becomes its own file (header included), named after the value with unsafe characters replaced. All files are generated in memory and downloaded from your machine — the original CSV never leaves it.

Why it's private

The CSVs that need splitting are usually the ones you cannot upload: a full customer export, a year of order history, a dataset with names and addresses. Splitting happens on the rows in your browser's memory — the file is read, cut, and re-saved locally, and the network tab stays empty the whole time.

Who needs this

Anyone whose upload form caps file size, analysts handing per-customer or per-region slices to a team, and developers feeding a script that chokes on single-million-row files.