Key features:

Scheduled scan support
Can create bootable rescue disk
Windows XP SP2/Vista/7 SP1/8/8.1/10
Requires Intel Pentium 4 / AMD Athlon 64 or better, 256MB RAM, 1.5GB free disk space

Avast! Free Antivirus comes with real-time anti-malware protection, a password manager and a tool to clean your browser of unwanted extensions, plugins and toolbars. It also prompts you to install Chrome, in what is perhaps the first ever instance of a free software product being bundled with a vaguely useful extra; if you don’t want Chrome, you should take care to deselect this at install time.

Unlike most free anti-virus suites, Avast requires you to register every year if you want to continue using it. This doesn’t cost you a penny and can easily be done from inside the Avast client. However, the annual renewal can confuse less technical users, so if you’re installing the software for a family member who can’t handle their own technical problems, this potential issue is worth bearing in mind.

Avast also takes this opportunity try to encourage users to switch to its paid-for version – something you’ll see time and again, since its client is peppered with Upgrade Now prompts.

The free version is a perfectly effective anti-virus tool, however, and proved to be one of the most capable free anti-virus suites in AV-TEST’s latest results. It performed with consistent 99.9% accuracy in scans against reference sets of malware and, in live exposure tests, 100% accuracy in March and 98.8% accuracy in April.

It also produced only one false-positive block of legitimate software from more than a million samples. However, it had a greater impact on system performance than many of its rivals, particularly when it came to downloading and launching applications.

Avast’s current interface is brighter and more streamlined than previous incarnations. Your protection status, indicating that Avast is working as it should be, is front and centre, along with a button to run an instant SmartScan. This checks for both malware and potential vulnerabilities, such as outdated software.

A bar at the top provides access to Avast’s other tools and settings. These include specific scans for performance issues or network threats and a free SecureLine VPN service that’s designed to provide an extra layer of protection when connecting to important services via poorly secured internet connections.

You also get the SafeZone secure browser; a TeamViewer or LogMeIn-like Remote Assistance tool that lets you invite a friend to remotely access your PC to help you resolve an issue; a bootable Rescue Disk creator that you can use to scan PCs that aren’t booting into their operating system properly; and a password manager. That’s a generous selection for a free product.

There are also options for a firewall and for running applications in a sandbox, but these just take you to an upgrade page encouraging you to subscribe to a paid-for version of Avast. Elsewhere in Avast’s settings, you can configure the program’s inbound and outbound email scanning, live detection and blocking of potentially malicious content in your web browser, plus access extra options such as a pop-up-free Gaming mode, an ultra-paranoid Hardened mode and the option of scanning for potentially unwanted programs such as non-malicious adware.

Avast’s Free anti-virus put in a solid performance in AV-TEST’s trials of both reference malware scanning and real-world live exposure protection. However, the company’s somewhat obtrusive registration system is confusing to inexperienced internet users and it has more of an impact on system performance than some of its rivals.