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User Ratings

ease 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 3 / 5
features 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 3 / 5
design 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 3 / 5
support 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 4 / 5

User Reviews

  • Perfect little program! It saves hundreds of people 1-2 minute download time every day (while updating my app). Reducing 11MB exe down to 4.3MB ;)

  • Regarding a previous review - the point is it saves space and when you use a folder full of dll's such as VST plugins a reduction from 2.5GB to 1.5GB is enough to make it worthwhile for me. Additionally, I've heard some programmers surprised that the decompressed program uses even less memory so in some cases it might be useful to reduce the ram footprint in specific cases. Also, since it's been recommended by many (including me, I rarely had issues, but some apps did not work - a minority by far) you can assume that your experiences are unfortunate and for the most part it is working for people. On a HDD system it also equates to reduced load times in many cases since a 60MB application down to a 25MB saves over 0.25 seconds - that's significant in some cases - and in others of course it's not so significant. I use UPX to optimise memory-cached applications also, reducing their footprint means you can fit more .exe and .dll in memory so they can be preloaded instead of fetched at the moment the user needs them. As I said - it's a great tool for specific cases - maybe not for everyone.. I love it and thanks for the 64bit support ;) About the rating system that is included when you review this app - you could have a rating for performance as well and one for stability.

  • Many people of the BlitzMax community recommended me to use UPX to save diskspace of my executable files my projects have, so I did. It's been a big deception from the start. Sure, nothing wrong with the compression ratio, but many programs refused to work properly after being packed by UPX, lots of them didn't even work at all. I gave it more chances hoping upgraded versions would ease the pain, but nothing. I guess I can't blame them. I've seen commercial programs like these suffer from the same issues. The only thing I could do was recompile my programs and tadaa, trouble gone. I guess the entire concept of executable packing just wasn't meant to be. And besides, the big issue with disk space is most often not coming from the executable files anyway, so why bother......

  • Broken or corrupt file.

  • Thanks for Upx, it's the best!

    1 user found this review helpful.
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Additional Project Details

Intended Audience

System Administrators, Developers, End Users/Desktop

User Interface


Programming Language

C++, Assembly