CCleaner tops our list of free registry cleaners for several good reasons. Aside from being completely free and working with all versions of Windows, two additional things really stand out.
For one, we’ve never had CCleaner cause a problem in the Windows Registry, which some less-well-done registry repair tools do on a regular basis. And two, because it’s optionally available in a portable format (i.e., it doesn’t need to be installed).
Read our full CCleaner review below for a list of features, pros & cons, my opinions on the program, and some basic instructions, or head straight to their download page linked above.
This review is of CCleaner v6.11.10435 for Windows, which was released on April 24, 2023. Please let us know if there’s a newer version we need to review.
What We Like
Multiple installation options
Keeps cookies that it knows you probably don’t want to delete (like webmail logins)
Unobtrusive context menu addition to the Recycle Bin
Long history of regular program updates (and can update automatically)
A backup file is created before any changes to the registry are made
Killer feature set
Can avoid scanning registry keys and values you tell it to skip over
Available as an Android and Mac app
What We Don’t Like
Standard download page is confusing and makes the program appear to cost money, which it does not
The regular installer will add another program to your computer unless you explicitly deny it
Advertises professional features in the free version
More About CCleaner
The most recent version of CCleaner works with Windows 11 and Windows 10, as well as older Windows operating systems like Windows 8 and Windows 7. It also runs on all versions of Windows 2008 and 2012 Server.
Four installation methods are available:
- “Latest official release” is the standard installer for the latest version, a full install of the program. It includes an option to also install another program (we’ve seen antivirus software here, and CCleaner Browser).
- “Official sunset release” is the standard installer for Windows Vista and XP users.
- “Portable,” which we recommend, doesn’t require installation at all.
- “Slim” is the same as the normal installer option, but without the additional software installation option.
CCleaner is actually more than just a registry cleaner tool. It’s probably more accurately called a system cleaner because it actually cleans a lot more than just your registry.
As far as the registry cleaning functions are concerned, CCleaner, like all registry cleaners, is primarily concerned with removing entries in the Windows Registry that refer to files, programs, or other resources that no longer exist.
For example, CCleaner will remove registry keys and registry values that point to programs and files that no longer exist in Windows. These abilities are exactly why running CCleaner, or another well-designed registry cleaner, is a great troubleshooting step when faced with a “missing file” or “cannot find a file” sort of errors, especially as Windows starts.
Specifically, CCleaner will remove registry entries that point to the following if they no longer exist: DLL files, file extensions, ActiveX objects, type libraries, applications, and application paths, fonts, help files, installers, software, MUI cache, sound events, and services.
Please download CCleaner from Piriform’s site only (CCleaner.com), which we’ve linked to at the top of this page! There are malicious programs that look and sound like CCleaner, but charge for the cleaning. Read more about this in our Registry Cleaners FAQ.
CCleaner Removes Files and Uninstalls Programs
Outside of the registry, CCleaner also removes temporary browser data like cookies, history, and the cache from all popular browsers. You can also do things like empty the Recycle Bin, clear MRU lists, empty the thumbnail cache in Windows, remove old memory dumps and log files, and much more.
CCleaner also has a Tools area where you can uninstall programs, view and change the programs that start up with Windows, find and remove files that are taking up lots of disk space, find duplicate files, remove restore points, and even wipe a drive.
Thoughts on CCleaner
If it’s not obvious already, we love CCleaner. It’s tiny, fast, and thorough. It doesn’t advertise to fix all the problems under the sun like so many “registry repair” tools do. It does what it does and that’s good enough. We like that.
We very much like that there are a few ways to “install” CCleaner. And while we’re usually a very big fan of portable programs, one advantage of actually installing CCleaner is the addition of Run CCleaner and Open CCleaner right-click options to your Recycle Bin. If you’re planning on using CCleaner for general system cleaning, this is a really handy feature.
My only real complaint about CCleaner is the confusing download page, which you can see here. While we link to their much more clear builds page elsewhere in this review, the standard CCleaner download page that most people end up on is a little confusing.
At first glance, their download page makes it looks like you have to pay for CCleaner if you want it to actually do something. We actually get regular emails about CCleaner being not free. However, it is free, but you can choose to pay for their Professional or Business Edition versions to get personal support, a software updater, and a few other features. CCleaner Free functions 100 percent and will not prompt you to pay for anything to clean up the registry or other files (but some of the settings in the free version only work if you have Pro).
It should be clear that while CCleaner is completely free, it’s only free for home users. Business versions of CCleaner are required if you plan to use the program in anything but a home/personal scenario.
Another trivial problem we have with CCleaner is that at the very start of the installer, you’re asked if you want to install another program along with CCleaner. We’ve seen another Piriform program and Avast! Free Antivirus advertised here but others might be, too. If you don’t want anything but CCleaner, just uncheck/decline whatever program is mentioned, and then continue installing CCleaner normally.
In summary, if you think a registry cleaner is necessary to solve some computer problem you’re having, we highly recommend you choose CCleaner. If you’re interested in some of the other really cool system cleaning features, know that among those programs, CCleaner is also probably your best bet. It’s simply a fantastic program.
How to Use CCleaner
CCleaner is easy to install. Just head to their builds page and choose the installation option you’d like.
Choose the standard installer or slim version to install CCleaner as you would any normal program. Pick the portable version if you’d like to run CCleaner from a flash drive or would just rather not install yet another program on your computer. You’ll need to unzip the program before running it in that case.
Once it’s up and running, follow these steps to clean the registry:
Select the Registry icon on the left.
Under the Registry Cleaner heading, make sure all of the options are checked.
If you have a good idea what you’d like CCleaner to “clean” from the registry then, by all means, limit the selection. For example, if you’re receiving an error when Windows starts about a program you no longer have installed, you could probably leave only the Run At Startup checked.
Choose Scan for Issues. CCleaner is done scanning your registry for unnecessary entries when the green progress bar at the top of the screen reaches 100%.
If you decide to cancel the scan midway through it—maybe because it’s taking too long to finish—you’ll still be able to fix what was found before you cancelled it.
Choose Review selected Issues.
While all of the registry entries that CCleaner found are checked by default, you can uncheck any entries you want to keep. One of the great things about CCleaner compared to its competition is that it doesn’t go overboard. You’re probably safe removing anything that it finds.
Select Yes on the dialog box that asks “Do you want to back up the registry before making changes?”.
If you aren’t asked about backing up the registry, you can make sure you are next time by enabling Show prompt to backup registry issues in Options > Advanced.
Choose an appropriate place to save the REG file and then pick Save.
This REG file can be used to undo the changes CCleaner is about to make to the registry. See How to Restore the Windows Registry if you later decide to use the REG backup.
On the next screen, choose Fix All Selected Issues.
You could also choose Fix Issue to remove every entry one at a time, but chances are you’re not sure which entries should be kept or deleted. Fortunately, CCleaner does a good job at determining that for you, so you’re best off just removing all of them at once, especially if there are hundreds or thousands.
Select Close after all the changes are complete. This might take just a second or two, up to several seconds, depending on how many registry keys CCleaner is removing or changing and how fast your computer is.
It’s now safe to close CCleaner or perform some other system cleaning task with the program.
It’s a good idea, however, to repeat the above steps again even if you’ve just completed a registry clean-up with CCleaner. A repeat scan is necessary since some items that were previously removed might create further objects that need to be removed, in which case only a second scan (or third or fourth, etc.) is necessary in order to delete those new orphaned entries.
If you run an additional scan and the results are the exact same as the prior scan (i.e., the same entries were removed in both instances), you can quit repeating the clean-up process. One reason this might happen is if a process needs those entries, and so the system is rebuilding them even after you delete them.
CCleaner is fully documented on Piriform’s website and is a great resource if you need some help.
Thanks for letting us know!