Files & Archives · Split & Join Files
Split a large file into parts and join them back, verified
Quick answer
Open Toolfox → Split & Join Files, drop a large file, choose a part size (100 MB by default) or a number of parts, and click Split File. You get numbered .001, .002… parts with a SHA-256 checksum list; later, drop the .001 part and click Join Parts to rebuild and verify the original. It runs entirely on your computer (Mac, Windows or Linux). Files are never uploaded.
How to do it
- Open Split & Join Files and drop a file.
- Choose Split by part size or by number of parts (up to 999).
- Click Split File. Parts go into a “name (parts)” folder.
- To join, drop the .001 part or the .sha256 file and click Join Parts.
Options you can set
- Action
- Split by
- Part size
- Number of parts
Good to know
- To join, pick the .001 part or the .sha256 file; the other parts must be in the same folder.
- Joining refuses missing parts, and checks every part and the result against the .sha256 list when it's there.
- The .sha256 file is standard: “sha256sum -c” verifies it, and the parts can also be joined without Toolfox: “cat name.0* > name” on macOS and Linux, or “copy /b name.001 + name.002 name” on Windows.
- At most 999 parts per file.
Split & Join Files FAQ
Can someone without Toolfox join the parts?
Yes. “cat name.0* > name” joins them, and “sha256sum -c” verifies them with the standard .sha256 file.
What if a part is missing or damaged?
Joining refuses missing parts, and checks every part and the result against the .sha256 list when it's there.
How big is 1 MB here?
1 MB is 1,048,576 bytes. The last part holds whatever is left.
Is Split & Join Files in Toolfox free?
Yes. Split & Join Files is one of 57 tools in Toolfox, a free app for Mac, Windows and Linux with no account, ads, limits or watermarks.
Does Split & Join Files upload my files?
No. Toolfox processes files on your own computer and works offline; your files are never uploaded.
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Updated 2026-10-18 · Toolfox v0.2.1