Split a large CSV into smaller files by row count or by number of parts, each keeping the header row and its own download button.. CSV Splitter is a free online tool from the ToolsRift Charts & Data Tools collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.
Load your CSV, choose split by rows per file or by number of files, set the number, then download each generated part with its own button.
Yes, when your file has a header the tool repeats it at the top of every part so each piece is a valid standalone CSV. That is what import tools and spreadsheet apps expect, so the parts open correctly without any manual fixing.
Split by rows when a system has an import limit, for example 500 records per upload. Split by parts when you want to hand the work to a fixed number of people or processes and do not mind how many rows each one gets.
The practical limit is your device's memory, since the whole file is held in the browser. Multi-megabyte files are fine on a normal laptop, and because nothing is uploaded there is no server-side size cap or transfer wait at all.