Split a large CSV file into multiple smaller files entirely in your browser. Split by row count or by number of output parts — headers are preserved in every output file.
Split by rows to produce files of a fixed size (e.g. 1,000 rows each), or split by file count to divide the data as evenly as possible into an exact number of parts.
The original header row is automatically copied into every output part so each file is immediately usable as a standalone CSV without any post-processing.