To clear the thumbnail cache on Windows 11, open Disk Cleanup (cleanmgr), tick Thumbnails, and click OK. File Explorer caches every thumbnail it has ever rendered in %localappdata%\Microsoft\Windows\Explorer, and on a PC with heavy photo and video folders this cache easily grows past 1 GB. Corruption in it — not just size — is why Explorer sometimes shows stale, wrong, or blank thumbnails. Clearing it reclaims space and forces a clean rebuild.
TL;DR
- Easiest fix: Disk Cleanup (
cleanmgr) › tick Thumbnails › OK. - For stubborn or corrupted thumbnails, delete
thumbcache_*.dbafter stopping Explorer. - The cache lives in
%localappdata%\Microsoft\Windows\Explorerand can exceed 1 GB. - Clearing it is safe — Windows rebuilds thumbnails automatically as you browse.
- Turn on Storage Sense to clear thumbnails on a schedule and prevent bloat.
What is the thumbnail cache in Windows 11?
The thumbnail cache is a set of database files where Windows stores small preview images of your photos, videos, and documents so File Explorer can display them instantly instead of re-rendering each one. The files are named thumbcache_*.db (alongside iconcache_*.db for icons) and live in %localappdata%\Microsoft\Windows\Explorer. The cache speeds up browsing, but it grows indefinitely and can become corrupted — producing blank icons, wrong previews, or Explorer crashes. Clearing it is a safe maintenance step; Windows regenerates each thumbnail the next time you open its folder.
The gentle method: Disk Cleanup
For most people, Disk Cleanup is all you need and it requires no restart.
- Press Start, type
cleanmgr, and press Enter. - Choose drive C: and click OK.
- Wait for the scan to finish.
- Tick Thumbnails (you can also leave Temporary files and Recycle Bin ticked).
- Click OK, then Delete Files.
Disk Cleanup removes the cache files safely without needing to stop Explorer. This both frees the space and clears mild corruption.
The forced method: deleting thumbcache_*.db
Use this when Disk Cleanup finishes but thumbnails still misbehave — wrong images, blank icons, or crashes.
- Open Task Manager (Ctrl + Shift + Esc).
- Find Windows Explorer, right-click it, and choose End task. The taskbar disappears — this is expected.
- In Task Manager, click File › Run new task, type
cmd, tick Create this task with administrative privileges, and click OK. - In the Command Prompt, run these in order:
cd /d %localappdata%\Microsoft\Windows\Explorerdel /f /q thumbcache_*.dbdel /f /q iconcache_*.db
- Back in Task Manager, click File › Run new task, type
explorer.exe, and click OK. The taskbar returns.
The next time you browse a folder, Windows rebuilds the thumbnail cache from scratch.
Disk Cleanup vs. manual deletion
| Situation | Method | Restart Explorer? |
|---|---|---|
| Just reclaiming space | Disk Cleanup (cleanmgr) |
No |
| Mild stale thumbnails | Disk Cleanup | No |
| Persistent blank or wrong thumbnails | Delete thumbcache_*.db |
Yes |
| Wrong app/icon images | Delete iconcache_*.db too |
Yes |
Is it safe to delete the thumbnail cache?
Yes. The thumbnail and icon caches contain only generated preview images — not your actual photos, videos, or files. Deleting them never touches your real data; Windows simply re-creates each thumbnail the next time you open the folder. The only short-term cost is that the first browse of a media-heavy folder will be slightly slower while previews regenerate. Ending the explorer.exe process temporarily hides the taskbar, but restarting it (step 5 above) restores everything.
How to prevent thumbnail cache bloat
- Open Settings › System › Storage › Storage Sense and toggle it On — Storage Sense clears thumbnails automatically on its schedule.
- Avoid setting File Explorer to Extra large icons on folders with thousands of media files; the cache balloons to match the larger preview size.
FAQ
Does clearing the thumbnail cache delete my photos?
No. The thumbnail cache only holds generated preview images. Clearing it never affects your actual photos, videos, or files — Windows just regenerates the previews when you next open the folder.
Why do my Windows 11 thumbnails show the wrong image or go blank?
That's almost always thumbnail cache corruption. Clearing the cache with Disk Cleanup, or deleting the thumbcache_*.db files for a forced rebuild, resolves stale and blank previews.
Where is the thumbnail cache located in Windows 11?
It lives in %localappdata%\Microsoft\Windows\Explorer, as files named thumbcache_*.db and iconcache_*.db. Disk Cleanup clears them for you, or you can delete them manually after stopping Explorer.
How much space does the thumbnail cache use?
On a PC with large photo and video libraries, the cache easily exceeds 1 GB. Heavy use of large icon views makes it grow faster, since Windows caches bigger preview images.
Will clearing the cache slow down File Explorer?
Only briefly. The first time you open a media-heavy folder after clearing, thumbnails regenerate and load a little slower. After that, browsing is back to normal speed.
Keep your C drive lean
With the thumbnail cache cleared, move on to the bigger space wins. Deep cleaning Windows 11 and 10 without third-party utilities is the full native routine, how to clear Delivery Optimization files removes leftover update downloads, and how to disable hibernation to save gigabytes of space reclaims a hidden multi-GB file. To understand where caches like this accumulate, read what is the AppData folder and can I delete it, and to find the biggest folders fast, use TreeSize Free or the cross-platform storage running out checklist. If your phone is the device that's actually full of photos and screenshots, Cleanor cleans it the same way — quickly and entirely on-device.