New feature request: Ebook brower mode


I did not search in the forum so it might be a duplicated one.

I’d like to have a brower mode or function:

  1. List thumbnails for all ebooks supported in a directory(current working directory), something similiar to FastStone viewer does for pictures
  2. User can search/filter by name or other infor if avalable

It’s useful for huge book collections.

I know CreateThumbnailForFile is the function to do most of the job. And the Remember opened files is most of the work.
I’m not sure if there were same requirements from others.


Those functions are usually part of an explorer and there were many that specialised in ebook view/convert have you considered calibre which also has a library system for queries?

SumatraPDF does have some thumbnail functions and remembers opened files but these are not its primary function.

There is an older list in the blog here and windows now has basic epub support built in see and


The function that Win 10 has is a preview. That is, you have to click on the icon of the file and enable preview for epub. And PDF(may be more) is not supported. The book itself is still shown as a icon.

For Calibre, you have to add your book into it manually.

Thumbnail function of SumbatraPDF is perfect. And the way of FastStone/ACDSee viewer handling image thumbnails is also nice. So, it’s good to have the functions combined.

BTW: I saw someone mentioned that “Prevew PDF” can be enabled during installing. How can I if I use portable version or compiled version by myself?


This is totally off topic to SumatraPDF and its intended use as a document viewer.

However to answer your last question

For ANY context handler such as a previewer to work in a PORTABLE way, it would need to be hooked into the workstream (e.g. registry) , then unloaded from registry prior to reboot/restart otherwise it would not be there for start-up next time. There are many such portable Apps Loaders/Unloaders but this is very case specific. I would look for portable versions of thumbnail explorers.


“portable versions of thumbnail explorers” is what I tried to find. There is a Golang version but it does not support PDF and save the thumbnails(slow to parse every time on startup).

Sumatra is a good one if it had a browser mode. I’m not sure if I had time to work on it. It seemed @kjk are actively working on Golang projects now.