Comodo Free Antivirus review

Feature-packed antivirus for expert users

TODO alt text

Our Verdict

Some powerful protection tools, but you'll need time, knowledge and experience to set them up.


  • Loads of features
  • Effective sandbox
  • Appealing interface
  • Highly configurable


  • No web filtering
  • Rarely checked by testing labs
  • Some features require expert knowledge

Comodo Free Antivirus is an unusually powerful antivirus tool which uses multiple security layers to keep you safe from harm.  

The package offers real-time protection to detect and block known malware before it can do any harm.  

If you run into an unknown or untrusted application, Comodo can run it in a sandbox to prevent it infecting your PC.  

You're able to run browsers or other legitimate applications in the sandbox, or even an entire virtual desktop, again making it very difficult for any threats to modify your PC or monitor what you're doing online.  

Knowledgeable users can enable and tweak a Host Intrusion Protection System, giving them a great deal of fine-grained control over what apps can do on your system. And if you're still concerned about a possible infection, Comodo Free Antivirus comes with some very useful bonus tools which allow you to investigate your system further.  

There is a notable omission in the lack of web filtering, which means the system doesn't block malicious URLs. But otherwise Comodo Free Antivirus delivers far more functionality than just about anything else, and the sandbox in particular could help stop even the very latest, undiscovered threats. 


Comodo's free antivirus is easy to find on the website, and we were able to download and launch the installer in a very few seconds.  

The package got off to a bad start, immediately offering to 'enhance' our browser experience by setting Yahoo! as our browser home and new tab pages, as well as making it our default search engine. This option is checked by default, too, so if you rush through installers, clicking Next without paying attention, you're likely to be affected. It's easy to avoid this - just clear the checkbox - but we would prefer Comodo didn't play with our browser settings in the first place, especially as this has precisely nothing to do with security. 

Fortunately, the installer also offers more relevant options, including the ability to install Comodo's secure Dragon Browser and set up your system to use Comodo Secure DNS.  

The setup process took a little longer than usual, and the post-installation scan was also far from speedy (updating the virus database took two minutes all on its own), but eventually Comodo Free Antivirus was up and running and we were ready to explore. 

Comodo Scan Types


Comodo Free Antivirus stands out immediately for its versatile and flexible interface. You can view your security status and launch scans from a tiny desktop widget, a more conventional antivirus console, or switch to an Advanced View which gives speedy access to Comodo's expert-level functions and features.  

You don't have to get involved in the complicated stuff, of course. Newbies can use the program much like any other antivirus - click Scan, choose a Quick or Full Scan and wait for the results - but life does get more interesting if you explore Comodo's other options.  

A Rating Scan, for instance, scans running processes and commonly infected areas and reports on the reputation of all the files it finds. This is interesting as it can show you files which aren't clearly malicious, but are considered untrusted (both executables and certificates), as well as files that Comodo hasn't seen before. If you suspect you've been infected by something nasty, but can't prove it, the Rating Scan may be able to point you in the right direction. 

Console detailed

Comodo can also scan specified files and folders, or you can set up multiple custom scans to carry out your choice of actions. These include the option to scan particular files and folders, the trusted root certification authorities store, the contents of RAM, commonly infected areas or the entire computer.

You're able to customise key settings for individual scans - the sensitivity of any heuristics checks, whether the scanner can connect to the cloud to query file ratings - and there's an unusually configurable scheduler. Comodo doesn't just enable running the scan daily or weekly at 4:30pm, for instance: it's just as easy to have your scan launch on Monday to Friday only, but only if the computer is idle and not running on battery.  

If all else fails, an option to create a bootable CD or USB flash drive should help you clean up even the most heavily infected PCs. 

Comodo's sandbox is an unusual highlight. In a click or two you're able to run suspect programs in a secure environment where they can't make permanent changes to your PC. Alternatively, run a browser in the sandbox and it will protect you from some web-based malware, while also limiting the ability of any malware which might be on your PC to monitor what you're doing. 

An option to install a complete virtual desktop gives you a complete isolated environment for maximum security. It's a welcome addition to the package, although the need to install Microsoft Silverlight to make it work seems a little, well, bizarre. Microsoft hasn't been developing Silverlight (other than adding security patches) since 2013, and Google Chrome hasn't supported the technology for almost three years.  

Comodo Dragon is a Chromium-based browser which comes bundled with Free Antivirus. This protects your privacy by cutting out the telemetry Chrome normally sends to Google, as well as blocking cookies, forcing HTTPS connections, looking out for dubious SSL certificates, and more.

Dragon does its job, but the package lags several released behind Chromium (our installed Dragon version during the review was 58, but Chromium was at 64), and, for us, there's not enough 'value added' to justify Dragon's existence. If you're concerned about Chrome, download and use Chromium instead and configure it for maximum security. 

Comodo Free Antivirus also supports a Host Intrusion Protection System (HIPS), a hugely powerful security layer which gives you vast control over what applications can do on your system. At a minimum it alerts you to potentially dangerous actions by untrusted programs - running an executable, for instance - and allows you to decide whether each of these should be allowed. 

Experts can go beyond this to define custom HIPS behaviour rules, although these can require a lot of low-level knowledge. Would you know the consequences of preventing a process setting Windows event hooks, for instance? Still, the HIPS is turned off by default, so newbies don't need to worry, and if you know what you're doing there's huge scope here for improving and fine-tuning your system security.

Advanced tasks

Other geek-friendly features include convenient integration with Comodo KillSwitch, a souped-up Task Manager with so many extras that it deserves a review all on its own. A single example: the KillSwitch Repair option makes it easy to see if malware has messed with your HOSTS file, DNS settings, Explorer policies and more, and can restore the defaults with a click.  

Comodo's Settings dialog rounds off the program with something for everyone. Beginners can choose a new theme for the interface, or disable update checking when the system is running on batteries. But more experienced types can customise how scans work, create new scan types, tweak the HIPS, and generally get involved in most of Comodo's low-level operations. 

Comodo HIPS


Comodo Free Antivirus isn't assessed by most of the independent testing labs, but AV-Test has checked Comodo's Internet Security Premium, and the results are interesting.  

Test results over the past couple of years have highlighted some major issues. Protection rates dropped to 95% in August 2016, for instance, while the August 2017 test revealed performance problems that are difficult to believe. File copying taking anything up to 256% longer when Comodo was installed? Really?  

But on the plus side, the February 2018 test showed the program protecting against 100% of threats, with no major performance issues (file copying slowdown was now less than average), minimal false alarms, and an excellent score of 17.5 out of 18. That was enough for AV-Test to award Comodo its Top Product award, one of only 7 packages to achieve that from a field of 18.  

While this looks good, it's not enough information to get a clear indication of Comodo's malware-hunting abilities. We would need to see more AV-Test results to be sure that Comodo really is improving, and it would be useful to see how the products performed in AV-Comparatives' Real-World Protection Test.  

AV-Test's latest test results are undeniably encouraging, though, and it's worth keeping in mind that even these don't give you a full picture of Comodo's protective abilities. The tests don't take full account of the power of Comodo's HIPS or smart use of the sandbox, and these could help you avoid infection, even if the engine doesn't detect the malware itself. 

Final verdict 

A powerful antivirus tool with some unusual and advanced features. There's little data on its accuracy, though, and you'll need real technical expertise to get the most from the program.