7-Zip

7-Zip is a free, open-source file archiver that opens almost everything and compresses tighter than most paid rivals. A plain interface is the only real cost.

WinRAR

WinRAR is Windows archiving software that compresses, encrypts, and repairs files, and its free trial never really shuts off. The real question is whether that beats 7-Zip.

CCleaner

CCleaner is a PC cleaner for junk files, browser traces, and uninstall leftovers on Windows, Mac, Android, and iOS. The free tier still does the real work.

Sumatra PDF

Sumatra PDF is a free, no-frills PDF reader that opens files on Windows almost instantly, without Adobe’s bloat. See who it actually fits.

LibreOffice

LibreOffice is a completely free, open source Office & Productivity suite covering six apps, though heavily formatted Word and Excel files don’t always translate perfectly.

Mozilla Firefox

Mozilla Firefox is a free, open-source web browser that runs on its own independent engine, built around strong privacy defaults and deep customization.