CCleaner on Windows does less than its reputation suggests
The best known PC cleaner, the open source alternative, and what both actually remove. With the free equivalents for each part.
CCleaner is the most recognised name in this category and its reputation was built on Windows XP. Understanding what it does today, and what the built in tools now do for nothing, makes the choice straightforward.
What it actually removes
| Feature | What it does | Free equivalent |
|---|---|---|
| Temporary files | Browser caches, temp folders, logs | Storage Sense and Disk Cleanup |
| Registry cleaner | Removes orphaned keys | Nothing, and nothing is needed |
| Uninstaller | A list of installed programs | Settings, Apps |
| Startup manager | Disables startup entries | Task Manager, Startup tab |
| Driver updater | Paid feature | Windows Update, and vendor sites |
| Performance optimiser | Paid feature | Not a real category |
The registry half
The registry cleaner is the feature the product is known for and the one worth ignoring. Orphaned keys are kilobytes, they do not slow anything down, and removing the wrong one breaks an application. It has never been necessary on any version of Windows that most people are running.
BleachBit, the open source option
BleachBit does the temporary file half without the registry theatre or the upsell. It is free, open source, and more configurable, which cuts both ways: its cleaner list includes options that will sign you out of things and clear data you wanted, and the tick boxes do not always make that obvious.
It also has a genuine feature the others lack: overwriting free space, which matters when you are preparing a machine to sell, though Windows' own reset with drive cleaning covers that case now.
What neither does
Neither shows you a folder tree. A 40 GB folder that fits none of their categories does not appear in either tool at any size, which is the same limitation the built in tools have and the reason a machine can report a few hundred megabytes of cleanable space while being genuinely full.
If you want one anyway
Read what it proposes to delete before confirming, particularly anything under AppData where an application's cache and its only copy of your data sit in the same folder. That advice applies to every tool in this category regardless of price, and the rest of it is in are PC cleaners safe.
Common questions
Is CCleaner safe on Windows?
It is mainstream software from a large vendor, and the risk is not malice but confidence about files it did not create. Its registry cleaner is the feature worth ignoring entirely.
Is BleachBit better than CCleaner?
It does the temporary file half without the registry cleaning or the upsell, and it is open source. It is also more configurable, which means its options can clear data you wanted if you tick without reading.
Do I need a registry cleaner on Windows?
No. Orphaned registry entries are kilobytes, do not affect performance, and removing the wrong one breaks software. No modern version of Windows benefits from it.
What is the best free alternative to CCleaner?
For temporary files, Storage Sense and Disk Cleanup, which are built in. For finding what is large, a disk analyser. For startup items, Task Manager. Each part has a free answer already on the machine.