JB Thumbnail Preloader Thumbnail Preloader
JB Thumbnail Preloader is a Windows app. You can buy your license right here on your phone; for the download itself, open this page on your Windows PC.

Help

Help center

Most questions come down to three things: the first launch, choosing folders, and the case where a preview does not appear. All of it is here.

The first launch

  1. InstallRun the installer and click through setup. It takes under a minute and needs no account.
  2. Add foldersPick the folders you actually work in. The preloader starts generating previews in the background right away.
  3. Open a folderIn Explorer switch the view to large or extra large icons. Your files show up as images instead of grey icons.
Important: Explorer only shows previews when the view is set to icons. In details or list view they stay icons, no matter what the preloader has already prepared.

How many folders make sense

Fewer is faster. Keeping an archive of hundreds of thousands of files warm is possible, but it costs time and disk space. In practice this is usually enough: the running job, the folder for freshly imported cards, and the directory you sort in. Older projects get picked up as soon as you open them.

Speed modes

ModeWhen to use it
SlowWhen you work on something demanding in parallel and want the preloader to stay unnoticeable.
NormalEveryday use. A good balance between pace and a quiet system.
FastWhen a freshly copied card should be ready quickly.
UltraShort bursts for big catch-up runs, for instance after moving your archive.

Studio governs the speed itself and adapts it to how busy the machine currently is.

When something is off

Missing previews almost always have one of a few causes. The fastest route is Troubleshooting. Licensing questions are answered in Manage your license.

Frequently asked questions

Does the app have to run all the time?

It works in the background and keeps your folders warm. If it is closed, previews already generated remain, but new files are no longer prepared.

Does the preloader slow my machine down?

It runs at low priority in the background. If you work on something demanding in parallel, pick slow mode and it stays practically invisible.

Does it work on external drives?

Yes, external drives are included in every plan. Network drives and NAS require Studio.

How much space do the previews need?

That depends on the number of files, not their size. Previews are small images, so a large archive typically lands in the range of a few gigabytes. The app shows how much space is used and cleans up on its own.