Help · Duplicates
The Duplicates screen finds copies of the same photo — including the resized and re-compressed ones that are not byte-identical — groups them, and lets you decide. This page explains each stage and, more importantly, what it does and does not do to your files.
Scanning and reviewing change nothing at all. Nothing leaves your disk until you press the button that says so, and what it does then is move the marked files to the Trash — not delete them. They sit there until you empty it, and Restore the last batch from Trash brings them back in one click.
FolioSort never decides on its own which copy dies. It suggests a keeper; you confirm.
Folder to scan · Include subfoldersFree
Point it at a folder, or at a whole drive. Scanning is free and unlimited on every tier, so you can always find out how much space the duplicates are costing you before deciding whether to pay for anything.
Do not point it at the inside of an Apple Photos or Lightroom library. Those apps own the files underneath and removing one behind their back leaves them with a broken reference.
The four stages you seeFree
The perceptual pass is the slow one, and the reason a scan of a big drive is not instant. It is also the only reason the tool finds the copies that are actually filling it.
Groups, and the keeperReviewing is free
Each group is one photo and the copies of it that were found. FolioSort marks one as the suggested keeper — the largest, sharpest, most complete version — and the rest as candidates. KEEP and DELETE on each thumbnail are yours to flip: "Kept — click to mark for Trash" and "Marked for Trash — click to keep" tell you which state you are looking at.
Click any thumbnail to enlarge it and compare properly. On a group of four near-identical shots that is the difference between a decision and a guess.
Apply suggestion · Keep only suggestedFree
Accepts FolioSort's choice for a group, or across everything the filter is currently showing. It marks; it does not remove. Nothing happens until you run the Trash step.
Space to freeFree
What the current selection would give back. It updates as you change your mind, and it is the honest answer to "is this worth doing".
Move to TrashPro beyond the free allowance
Moves everything marked DELETE to the system Trash. The free tier cleans up to 20 copies in total; scanning and reviewing stay unlimited. Nothing is bypassed, shredded or deleted outright.
Move to Folder…Pro
Collects the marked copies into a folder of your choosing instead of the Trash — for when you want to look at them for a week before letting go.
Restore the last batch from TrashFree
Undo for the last removal, straight from this screen. The same batch is also in Activity with everything else.
It found nothing, and I know there are duplicates
Check the folder and that Include subfolders is on. If the copies live on a different drive, scan a parent folder that covers both — or use Merge, which is built for exactly that case and de-duplicates while it combines.
It grouped photos that are not the same
Perceptual matching groups by what the picture looks like, so a burst of near-identical frames can land in one group. That is the point, and it is why nothing is removed without your confirmation — keep them all, or use Best Shots, which is built for choosing between frames rather than copies.