01
Choose only the first numbered part
Add the .001 file and Foldout gathers the sequential sibling parts automatically, keeping the receiving workflow short even when a large file arrived in many pieces.
Join FileFile Tools
Rebuild a split delivery from its first numbered part.
Join File is the receiving side of Foldout's large-file handoff. Add the .001 part and Foldout discovers the remaining numbered siblings in order, validates the reconstructed bytes against the SHA-256 sidecar when one is present, and writes the complete original filename beside the parts.
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What it does
Gather numbered parts automatically and reconstruct the complete file with optional checksum verification.
Start with the .001 part instead of selecting every piece manually.
Gather sequential sibling parts in the correct order.
Verify the reconstructed bytes when a SHA-256 sidecar is available.
Write the complete original filename without changing the numbered parts.
Open, reveal, copy the path, undo, or review the result in Output Center.
See the transformation
Gather numbered parts automatically and reconstruct the complete file with optional checksum verification.
Start with the .001 part instead of selecting every piece manually.
02
Finish with a verified, complete file
When a SHA-256 sidecar is present, Foldout checks the reconstructed bytes, writes the original filename, and keeps reveal, undo, and Output Center actions beside the successful result.
Why it belongs
Why Join File earns a place in the toolbox.
The practical details that make this job faster, clearer, or safer than doing it by hand.
One part is enough to begin
The .001 filename identifies the set; Foldout locates .002, .003, and the rest beside it automatically.
Integrity can be proven
A matching .sha256 sidecar turns reassembly into a byte-for-byte verification instead of a hopeful concatenation.
The pieces remain untouched
The reconstructed file is written as a separate output, leaving every numbered source part available for another transfer.
The result is ready to use
Open or reveal the complete file immediately, copy its path, or inspect the completed operation in Output Center.
How to use it
From opening the tool to saving the result.
- 01
Place all numbered parts and the optional checksum sidecar together.
- 02
Add the .001 part to Join File.
- 03
Run Join and let Foldout gather and verify the sequence.
- 04
Open or reveal the complete reconstructed file.
Questions
Before you try Join File
Do I need to select every numbered part?
No. Select the .001 file; Foldout gathers the sequential sibling parts from the same folder.
How is the result verified?
When the split set includes a SHA-256 sidecar, Foldout checks the reconstructed file against it before reporting success.
Are the numbered parts deleted?
No. Join File writes a separate reconstructed file and leaves the source parts unchanged.
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