About this tool
Record exact file-byte evidence with portable root-independent paths, then inspect every difference from a saved baseline without uploading the folder.
Folder Checksum & Integrity Verifier reads every file in a folder you select, computes a SHA-256 digest for each one, and writes the results into a JSON manifest keyed by relative path. Because the selected root folder's name is stripped, the same content produces matching paths whether it lives on a desktop or a network share. Load a previously saved manifest as a baseline and the tool compares the current folder against it, sorting every path into one of five states: Added, Modified bytes, Metadata only, Removed, or Unchanged. It handles up to 1,000 files, 100 MB per file, and 500 MB in total, and a baseline JSON up to 10 MB. The comparison report can be downloaded as JSON for a record of exactly which paths changed.
- Removes the selected root name, validates portable relative paths, blocks normalized cross-platform collisions, and hashes up to 1,000 files, 100 MB each, and 500 MB total.
- Validates version 1 SHA-256 JSON or identifies a compatible legacy files-only baseline before comparing any path.
- Separates added, modified bytes, metadata-only, removed, and unchanged paths, exposes both hashes for byte changes, and exports complete manifest and comparison evidence.
How to use Folder Checksum
Click Choose folder and pick the directory you want to inventory. A progress bar shows hashing, and Cancel stops after the file currently being digested finishes. When it completes, click Download manifest to save folder-manifest.json; that file is the baseline you will compare against later. To check a delivery or a later copy, choose the new folder, then use the Baseline manifest picker to load the saved JSON. The summary shows counts for Added, Modified, Metadata only, Removed, and Unchanged, and the Evidence filter dropdown narrows the table to one state. Rows with byte changes show both the current and baseline hashes. Only the first 500 filtered rows are displayed, but Download comparison writes folder-integrity-comparison.json with every path included.
When this tool is useful
- A release manager confirming that a build folder handed to QA is byte-identical to the one that was signed off.
- A translator or agency receiving a batch of source files who needs to prove which ones the client changed between rounds.
- An archivist recording a checksum inventory of a document set before it is copied to long-term storage.
- A developer checking whether a vendor's updated SDK drop actually changed any binaries or only touched timestamps.
- A photographer verifying that a backup drive holds the same RAW files as the working folder after a copy job.
Practical tips
- Keep the manifest somewhere separate from the folder it describes. A baseline stored inside the folder can be replaced along with the files it was meant to check.
- Metadata only means the bytes and size match but the modified timestamp differs, which is common after a copy or sync; it is usually not a real change.
- Empty directories, symlinks, permissions, and hidden files the browser picker skips are not in the manifest, so it is not a full filesystem snapshot.
- Each file is loaded into memory to hash, so on a low-memory device stay well under the 100 MB per-file limit and split very large trees.
- A matching manifest shows the bytes are equal to a baseline you trust. It is not a signature, a virus scan, or proof of who produced the files.
Examples you can test
Load an example, compare the result with the expected output, then replace it with your own input.
Compare a release candidate to the approved build
Example input
Baseline from build 1.4.0 plus a new folder where one file was edited, one added, and one deleted
Expected output
Summary: Added 1, Modified 1, Metadata only 0, Removed 1, Unchanged 212, with both hashes shown for the modified path
Filter to Modified bytes first, then Removed, since those are the paths that need an explanation before the build is accepted.
Check a backup copy
Example input
Baseline from the original photo folder; comparison run on the copy on an external drive
Expected output
Every path Unchanged or Metadata only
Timestamps often shift during a copy, so a Metadata only result across the board is the expected sign of a clean backup.
Validation checklist
- Confirm the folder you selected is the intended root, since paths are relative to it.
- Check the file count against the 1,000-file and 500 MB limits before hashing.
- Review every Modified bytes and Removed path before accepting a delivery.
- Download the comparison JSON when more than 500 rows match your filter.
- Keep the baseline manifest and the comparison report together with their dates.