Split a Large File into Chunks with split -b
Cut multi-GB files into fixed-size pieces for transfer or storage limits.
Run `split -b 1900m bigfile.iso part-` to produce part-aa, part-ab, … each under 2 GB.
01Command
Command
$ split -b 1900m 大文件.iso 分块-02What it does
`-b` accepts k, m, or g sizes; output files get sequential suffixes after your chosen prefix. This is the reliable way around FAT32’s 4 GB limit on USB drives, or email/upload caps. Reassemble losslessly with `cat` — the pieces are plain bytes.
03Risk
!Warning: Keep the pieces and prefix name together until rejoined; renaming pieces breaks the default alphabetical order. Use `-a 3` if you need longer suffixes for very many chunks.
04Undo
✓No undo needed — this command does not change persistent state.
05Sources
- split – Split a file into piecesEvidence: Documents -b byte size split and numeric suffix options
Last verified: 2026-09-18 · Category: Files & Folders
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