Online services · review
CCleaner
CCleaner is Piriform’s long-running Windows cleanup utility, now published under Gen Digital, the same corporate parent as Avast, Norton and our separately reviewed Recuva. It clears temporary files, browser data and startup clutter competently. Two things any honest review has to cover: a 2017 breach that shipped malware inside a signed CCleaner installer, and the now-common finding that its signature registry cleaner does little measurable good on a modern Windows PC.
Last reviewed 24 August 2026 · scored 3.7/5 by our editors
- First released
- 2003
- Owner
- Piriform / Gen Digital
- 2017 incident
- Malware in installer
- Registry cleaning benefit
- Minimal on modern Windows
About CCleaner
CCleaner was created in 2003 by Piriform, a small British software company, and became one of the most downloaded Windows utilities of its era. Avast acquired Piriform in July 2017; Avast itself merged with NortonLifeLock in 2022 to form Gen Digital, which is also the publisher of Recuva, AVG and Norton. That ownership history is not a reason to distrust the product on its own, but a buyer choosing between CCleaner and other cleanup tools should know the group it now sits inside.
The core product is a junk-file and browser-data cleaner with a startup manager and, in the free tier, a registry cleaner. It does what it says: it finds temporary files, cache and leftover installer debris and removes them, and it can disable programs launching at boot. Independent testing of the registry cleaner specifically has found that clearing the "issues" it flags produces no measurable performance change on modern Windows, and Microsoft does not recommend registry cleaning as routine maintenance at all — a fact CCleaner’s marketing does not lead with.
Professional adds the things that matter for unattended maintenance rather than deeper cleaning: scheduled automatic cleaning, a software updater, real-time monitoring and priority support. It does not clean more thoroughly than the free tier — the underlying engine is the same. Buying it is a bet on convenience and automation, not on a better clean, and a step worth taking only once the manual routine of opening Free and clicking clean has actually become a chore rather than an occasional five-minute task.
Plans and what they actually add
Free
$0
Junk-file and browser cleaning, startup manager and the registry cleaner, run manually. No scheduling, no automatic updates and no real-time monitoring — you have to open it and click clean.
Professional
around $30–45 a year, one device
Adds scheduled automatic cleaning, an automatic software updater, real-time monitoring and priority support. Does not clean more deeply than Free — the engine is identical.
Professional Plus
a higher annual price, multi-device
Bundles CCleaner Professional with other Piriform tools, including Recuva and Defraggler, across several devices. Only worth it if you actually want those other tools — buying it purely for CCleaner overpays for features you will not use.
ccleaner.com geolocates its checkout to local currency, and independent trackers disagree on the exact current dollar figure, so treat the Professional price below as a range rather than a fixed number — confirm it in your own market before quoting it in ad copy.
What works
Does the basic cleanup job reliably
Temporary files, browser cache and leftover installer debris are cleared competently, and the startup manager is a genuinely useful way to see and disable what launches at boot without digging through Task Manager.
Free tier is not artificially crippled
Free includes the registry cleaner and full manual cleaning, not a stripped demo. The paid tiers add automation and monitoring rather than gating core cleaning behind a paywall.
A long operating history under a large security company
Two decades in the category, now backed by Gen Digital’s infrastructure and support organisation, which handles the automatic-update and monitoring plumbing behind the paid tiers.
Lightweight and fast to run
It is a small, quick utility rather than a heavyweight suite. Scanning and cleaning a typical drive takes minutes, not the tens of minutes some "PC optimiser" competitors demand.
What doesn’t
A real, documented supply-chain compromise in 2017
Version 5.33, distributed between mid-August and 12 September 2017, was modified to include the Floxif malware and affected an estimated 2.3 million installs before Cisco Talos discovered it. A genuine breach, not a rumour, though a resolved, historical one.
The registry cleaner does little measurable good
Independent testing has found clearing the "issues" CCleaner’s registry cleaner flags produces no measurable performance change on modern Windows. Microsoft does not recommend registry cleaning as maintenance, and the feature implies a fix it rarely delivers.
Professional buys automation, not a better clean
Scheduled runs, an updater and real-time monitoring are the entire pitch for paying. Anyone expecting Professional to find and remove more than Free is buying on a false premise — the underlying cleaning engine is unchanged.
How it scores elsewhere
Aggregate public scores, with the source named. We do not publish individual testimonials — we have no way to verify them.
G2
⚠️ figure surfaced via search indexing during research, not confirmed on a live G2 page fetch — re-verify before use
4.5ReviewKong editorial score
our composite: a reliable, honest free cleaner, weighed against a real 2017 breach and a headline registry-cleaning feature with little proven benefit
3.7
Buy it if
- Windows users who want a fast, no-frills junk and browser cleaner
- Anyone happy running a manual clean occasionally rather than paying for automation
- People who also want Recuva or Defraggler and would rather buy one bundle than several tools
- Users comfortable evaluating a security incident from 2017 in context rather than avoiding the brand outright
Skip it if
- Anyone buying Professional specifically expecting a deeper clean than Free provides
- Users hoping registry cleaning will meaningfully speed up a modern Windows PC — the evidence does not support that
- Anyone who wants a publisher untouched by a past security incident, even a resolved one — Gen Digital’s other brands share the same 2017 history through Piriform
CCleaner: common questions
Is CCleaner still safe to use after the 2017 hack?
Yes. The 2017 compromise affected one specific version (5.33) distributed for about four weeks before Cisco Talos discovered it and Piriform shipped a clean build within a day of being notified. There is no evidence of a repeat incident since, and the response — a public disclosure, a fixed build and law-enforcement cooperation — is the standard playbook for handling a supply-chain breach. It is a real historical event worth knowing, not an ongoing risk.
Does registry cleaning actually speed up my PC?
Independent testing has found little to no measurable performance improvement from clearing the issues CCleaner’s registry cleaner flags, and Microsoft does not recommend registry cleaning as routine maintenance. It is not dangerous in normal use, but do not expect it to be the fix for a slow PC.
What does Professional actually add over Free?
Scheduled automatic cleaning, an automatic software updater, real-time monitoring and priority support. It does not clean more thoroughly — Free and Professional share the same cleaning engine under the hood. Professional is a convenience and automation purchase, not a deeper-clean purchase, and buying it expecting the latter is a common source of disappointment.
Is CCleaner the same company as Recuva?
Yes. Both are published by Piriform, which has been part of Gen Digital since Avast’s 2017 acquisition and Avast’s later 2022 merger with NortonLifeLock. If you already use one, the other comes from the same team and, on Professional Plus, can be bought bundled together.
Should I use the registry cleaner at all?
It is unlikely to cause harm in normal use, since CCleaner backs up changes before applying them, but the realistic benefit on a modern Windows installation is close to zero. If you want CCleaner mainly for temp-file and browser cleanup, you can safely ignore the registry section entirely.
Ready to try CCleaner?
Owned by Gen Digital, publisher of Norton, Avast and AVG · 2017 breach was publicly disclosed and fixed within a day of discovery · Registry-cleaning changes are backed up before being applied