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Split
split & re-join files
build v6.0
Break a big file into smaller numbered parts to slip past upload or email size limits, then join the parts back into a byte-identical original on the other side. It's a plain binary split (like classic split/HJSplit) — the parts aren't compressed and aren't usable until rejoined. Nothing is uploaded.

Drop a file

or click to choose the file to split

Splitting reads the file in slices without loading it all into memory, so large files work; parts are named name.001.part, name.002.part and so on. Join sorts by that number and concatenates — keep all parts together and don't rename them. The rejoined file is bit-for-bit identical to the original. Everything runs on your device.