Reset the Quick Look Thumbnail Cache with qlmanage

Clear stale Finder preview thumbnails without touching your files.

macOSqlmanagecleanupFinderquicklookLow risk

Run `qlmanage -r cache` to purge the Quick Look thumbnail cache, then relaunch Finder if needed.

01Command

Command

$ qlmanage -r cache

02What it does

Quick Look caches rendered previews so Finder can show them instantly. When previews go blank, show outdated content, or a new Quick Look plugin was installed, clearing the cache forces Finder to regenerate thumbnails from the real files. `qlmanage -r` alone resets the generator (plugin) cache, while `-r cache` wipes stored thumbnails.

03Risk

RiskLow risk

!Warning: Finder will need to re-render previews for a short while, briefly increasing CPU use. This only affects previews — no documents are modified or deleted.

04Undo

✓No undo needed — this command does not change persistent state.

05Sources

qlmanage – Quick Look server tool
ss64.com · technical · 2026-09-17
Evidence: Documents -r (reset generator cache) and -r cache (clear thumbnail cache)

Last verified: 2026-09-18 · Category: System & Settings

06Related solutions

Show file extensions for all files on Mac

macOSFilesFinderdefaults

Make Finder display .pdf, .docx, .png and every other extension at all times.

Medium risk ✓ 2026-09-16

Show the hidden Library folder on Mac

macOSFinderHidden files

Permanently reveal ~/Library — where app settings, caches and support files live.

Low risk ✓ 2026-09-16

Show the path bar in Finder on Mac

macOSFinderdefaults

Permanently display the full folder path at the bottom of every Finder window.

Medium risk ✓ 2026-09-16