CSV Splitter

About this tool

Large CSV files are hard to work with: spreadsheets stop at about a million rows, imports time out, and email and upload forms enforce size limits. This tool cuts a CSV into smaller files, either a set number of files or a set number of rows per file, and can repeat the header row at the top of each piece.

Everything runs in your browser. The file is read into memory on your device and is never uploaded.

Example

Input (header + 6 rows), split into 3 files with the header repeated:

orders_part1.csv        orders_part2.csv        orders_part3.csv
id,item                 id,item                 id,item
1,pen                   3,ink                   5,clip
2,pad                   4,tape                  6,glue

How it works

• By number of files: the data rows are divided as evenly as possible. If there are fewer rows than files you asked for, you get one file per row.
• By rows per file: every file gets that many data rows, except the last one, which gets what is left.
• Line breaks inside quoted fields are respected, so a multi-line cell stays in one record instead of being cut in half.
• Blank lines are dropped. Any delimiter works (comma, tab, semicolon), because the tool only looks at line breaks and quotes, not at the columns.
• The files are named after your original file, for example orders_part1.csv. You can download them one by one or all together as a ZIP.

Limitations

• UTF-8 only. The file is read as UTF-8 and written as UTF-8. If it was saved in another encoding such as Windows-1252 or Shift_JIS, accented or non-Latin characters will look garbled. Re-save the file as UTF-8 first.
• The whole file is loaded into your browser's memory, so very large files (hundreds of megabytes) may be slow or fail on devices with little memory.
• The tool does not check that every row has the same number of columns.

FAQ