What "similar" means

Similar files look, sound, or read like each other but are not byte-for-byte identical — an image re-saved smaller, the same song at a different bitrate, a document exported twice. The Duplicates tab never shows these, because they are not the same file. Similar files is where they live.

The trade is exactness for reach. A duplicate is a fact. A similar match is an opinion, and Trawler treats it as one: it groups the candidates and then stops, leaving every decision to you.

Duplicates and Similar files answer different questions

Duplicates Similar files
What it finds Files with identical contents Files that resemble each other
Certainty Confirmed Advisory — you judge each one
Picked for you Trawler can pre-pick copies to remove Never. Nothing is ticked for you
Replace with hardlink Offered Not offered

It needs a finished scan first

Similar matching reads the results of a scan. It does not search your drives itself. Run a scan before you open Similar files, or the match reports "No active session. Run a scan first."

That also means the scan's own filters apply. If the scan skipped a folder or a file type, nothing in it can appear here.

There are two ways in:

  • Before the scan. On Home, under Include similar items, tick the categories you want — "Tap to add look-alike categories to this scan." The matching then runs as part of the same pass, and the results are waiting when it finishes.
  • After the scan. Go to Similar files, pick a tab, and use its action — Find similar images, Find similar documents, Find similar audio, Find similar videos.

Four tabs

Images · Documents · Audio · Videos, in that order across the top.

Audio is one tab that holds two different matching methods — by tags and by sound. Which one you want depends on your library, and picking the wrong one is the single most common reason a music search comes back empty. See Audio.

Videos needs FFmpeg installed before it can run. See Videos.

Nothing is selected for you

Every Similar tab carries the same notice, headed You choose what to remove:

"Similar files aren't exact copies. Mark each one you want to remove — nothing is selected for you, and Replace-with-hardlink isn't available here."

Dismissing it on one tab dismisses it on all four.

That is a rule, not a default. No auto-pick runs on Similar results, and marking one member of a group never marks the others.

Replace with hardlink does not apply to similar files, for a plain reason: it makes two files share one set of contents, which is only safe when the contents are already identical.

The option is still offered in the processing list — it is not hidden — but it acts only on confirmed exact copies, so anything you ticked on a Similar tab is quietly left alone. If every file you ticked came from a Similar tab, choosing it does nothing at all. Pick one of the other four instead.

Once you have ticked what you want gone, use Process marked… and continue exactly as you would for duplicates — Archive to ZIP, Move to Recycle Bin, Delete permanently and Move to another location all work the same way. See Processing.

Exclude duplicates

The Exclude duplicates tick in the Matching bar is on by default:

"100% matches are already in the Duplicates pick list. Turn off to also show files you've already picked."

So a Similar tab hides files you have already ticked for removal on the Duplicates tab, rather than listing them twice. Turn it off when you want to see everything in one place.

The free version shows ten groups per tab

Above ten, the rest are counted but hidden: "N more groups — unlock the full version to view all results." The count in the header is the true total, not the visible one.

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