AZ Tools

File Splitter

File

Drop a file, pick a chunk size in MB, and split the file into numbered parts you can download one by one or all at once. The split runs locally with Blob.slice, so even gigabyte-sized files never leave your device. Use it to squeeze through email attachment limits, chat upload caps, or USB filesystem constraints.

How to use

  1. Drop or choose a file.
  2. Pick a chunk size — 25 MB is a common Gmail-friendly default.
  3. Click Split to create the parts.
  4. Download parts individually or all at once.

Frequently asked questions

How do I rejoin the parts?
On macOS / Linux: 'cat file.part01of04 file.part02of04 … > original'. On Windows: 'copy /b file.part01of04+file.part02of04+… original'.
Is the file uploaded?
No. Splitting uses Blob.slice in your browser, so nothing leaves your device — even multi-gigabyte files.
How big a file can I split?
There's no hard cap, but your browser has to keep blob references in memory. Several GB usually works; if a download fails, try a smaller chunk size.
Is the order important?
Yes — parts must be rejoined in order. The filename includes 'partXX of YY' to make the order explicit.

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