Duplicates and Undo
BatchFile Organiser can identify exact duplicate files and help you keep only the copy you want.
How duplicate detection works
A duplicate group is a set of two or more files with identical content.
The app narrows candidates by file size first, then confirms exact duplicates with SHA-256 hashing. If two files land in the same duplicate group, their contents match exactly.
What you can choose
For duplicate groups, you can use one of these presets:
- Keep Newest
- Keep Oldest
- Keep Largest
- Keep Smallest
You can also manually override any group and choose the exact file you want to keep.
What the preview shows
Before applying changes, the preview shows:
- Which file from each duplicate group will be kept
- Which copies will be removed
- How much storage space will be recovered
This lets you verify your choices before anything changes on disk.
What happens during apply
When you apply changes:
- Files being organised are moved into their new folders
- Duplicate copies selected for removal are moved aside as part of the undo system
This is important because it means the app can restore them during undo.
How undo works
After a completed run, the summary screen offers Undo.
Undo restores:
- Files moved during the last operation
- Duplicate copies that were removed during the last operation
Undo works on the most recent operation only.
Tips for safer duplicate review
- Prefer Keep Newest when you’re cleaning working folders with revisions
- Prefer Keep Oldest when you want the earliest original copy
- Use manual override when filenames are similar but context matters
- Review duplicate groups carefully before applying changes in folders with important personal files