A safe Windows cleaner. I clear out the big and the meaningless, I leave your passwords and data alone, and everything is reversible.
This help is public (on the web); the app only links to it from the "?" buttons.
No scare tactics, no "1247 registry errors". Just honest numbers and an explanation of why each action is safe.
The easiest way is to download the installer from the website. If you
prefer the command line, Viktor is also in the winget catalog — just run this in PowerShell
or Command Prompt:
winget install MichalFoist.ViktorTheCleaner
For admins and company rollouts (Intune, GPO, SCCM) there's also an MSI package on the website.
Viktor can check on its own whether a new version is out — by default it looks once a week (at startup, it only reads a public list of versions and attaches a random number identifying this installation, so the running copies of Viktor can be counted — it reveals nothing about you or your computer). You switch the frequency by clicking "updates: …" in the bottom right (manually / daily / weekly / monthly, plus "Check now"). When there's something new, a golden "New version … ▸" link shows up at the bottom — clicking it offers to download and install the new version right away. Viktor checks the signature of the downloaded file, closes for a moment and then starts again by itself. You can decline the offer and download it from the web by hand. Nothing downloads or installs by itself; you always have to click.
Viktor speaks six languages (English, Czech, German, French, Spanish, Polish) and picks one at startup based on your Windows language. If you want another, click the globe next to the golden coin on the main screen and choose — the choice is remembered and applies right away, no restart. "Automatic (by Windows)" restores the default behaviour.
Viktor is free, no ads, no tracking. If it makes you happy, you can chip in for further development — the golden coin on the main screen opens a window with a QR payment (scan it in your mobile banking, the account and amount are pre-filled) plus Revolut and PayPal links. Everything works offline, nothing is sent anywhere.
Viktor can send a message straight from the app — after a few cleanups he asks how he is
doing. Nothing is sent until you click Send yourself.
You can optionally attach a list of folders Viktor does not clean yet. It helps write
new rules: Viktor only knows the programs he sees on the author's computers, so he would
never learn about an app nobody there has. The Show what will be sent button lets you
read the whole text before it leaves.
Your user name is stripped from the paths — instead of C:\Users\you\AppData\Local\Something
it sends %LOCALAPPDATA%\Something. Only folder names and their sizes go out, no files
and nothing from inside them. Untick the box and nothing is attached.