Avast! Free Antivirus Review: Fast, Free and Fun

Avast Free Antivirus provides the two things you really want in a free AV program: a good level of security and a light system impact. It also tops the competition when it comes to adding accoutrements that other antivirus makers charge for, such as a password manager and a secure web browser.

In other words, Avast Free Antivirus puts the free in freemium, and it's for those looking for a little extra from their free AV software. We wish Avast offered slightly quicker scans, but overall, it's our Editor's Choice.

Costs and What's Covered

Avast Free Antivirus runs on Windows XP (with Service Pack 3) through Windows 10. It includes a password manager, a secure browser and a local-network scanner.

Avast has two paid-upgrade antivirus products. Starting at $60 per year, Avast Internet Security adds a ransomware shield, a personal firewall and stronger protection against phishing attempts and malicious websites and a personal firewall.

Avast bridges the gap between freemium and premium products with a password manager, a stand-alone hardened web browser and a network scanner.

Avast Premier, starting at $80 per year, adds a file shredder and an automatic software updater for third-party programs. (The free version tells you what's out of date, but doesn't update it for you.)

Antivirus Protection

Avast Free Antivirus starts with a traditional signature-based scanner that compares software against a database of known malware. To stop unknown malware, Avast's Behavior Shield heuristic monitoring watches how each new piece of software acts. Anything suspect gets uploaded to Avast's cloud servers for analysis and a possible addition to the malware-signature database.

Avast software collects information from the systems of 400 million users as part of the malware-analysis process, but you can opt out at the bottom of the Settings/General/Privacy page.

Avast Free Antivirus has browser-monitoring extensions for Microsoft Internet Explorer, Google Chrome, Mozilla Firefox and Opera. It also scans email attachments.

Forget about getting a personal firewall with Free Antivirus; that's reserved for the Internet Security and Premier products. The app does have specific defenses for threats from email, the web and malware.

Avast's malware engine does a very good job at sniffing out and destroying malware, although Bitdefender is even more effective.

You can manually start a full malware scan of the entire hard drive, or a SmartScan that looks for malware in key locations and for software vulnerabilities, outdated browser add-ons, weak passwords and home network vulnerabilities. Any file, folder or external drive can be scanned either through Avast's interface or with a right-click in Windows Explorer. But Avast Free Antivirus doesn't automatically scan a new drive as it's connected.

There's also a recently added Game Mode that suspends scans and notifications. You can customize the protection by setting the rootkit scanner to run during startup, or to scan for potentially unwanted apps, or even to turn off pop-ups — but you can't turn off the low-key suggestions to upgrade to Avast's paid software.

Antivirus Performance

Avast's malware engine does a good job at sniffing out and destroying malware, although Bitdefender is even more effective.

In Windows 10-based evaluations conducted by German independent lab AV-TEST in May and June 2017, Avast Free Antivirus' signature-matching scanner heuristic monitoring detected 100 percent of previously unseen zero-day malware.

Its signature-matching scanner caught 99.8 percent of widespread known malware in May, and 99.9 percent in June. Avast misidentified three harmless pieces of software — false positives — over both months, an acceptable rate.

Avast's stablemate AVG AntiVirus Free, which uses the same malware-detection technology, got exactly the same results. Bitdefender detected 100 percent of both widespread and zero-day malware over both months, with five false positives.

Avast's Windows 7 protection was about the same, with perfect scores against zero-day malware in January and February 2017. It also detected 100 percent of widespread malware in January, but the effectiveness dropped a bit to 99.9 percent in February.

The software had a single false positive over both months. Its detection scores matched Bitdefender's and came out ahead of the rest.

In tests conducted by Austrian lab AV-Comparatives on Windows 7, Avast Free Antivirus was slightly less effective. Facing an array of malicious websites, it stopped 99.1 percent of malware in March 2017, 99.6 percent in April and 100 percent in May.

Again, AVG had identical scores, right down to the handful of false positives. But Bitdefender and Panda each aced March and April, and got 99.7 percent in May.

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Security and Privacy Features

Avast Free Antivirus may not cost anything, but it bridges the gap between freemium and premium products with a password manager, a stand-alone hardened web browser and a network scanner, called Wi-Fi Inspector, that looks for vulnerabilities on other devices. Most of the competition require a premium upgrade to get such features.

Wi-Fi Inspector can tell you what's wrong with your router's setup, including vulnerable settings. It took about 5 minutes to find most of my connected devices and provided useful information about outdated firmware and weak passwords, but can't fix the faults – you'll have to do that yourself.

Avast Passwords is an extension for Mozilla Firefox, Google Chrome and Avast's own SafeZone browser, and has complementary Mac, Android and iOS apps. It stores an unlimited number of passwords across an unlimited number of devices, generates new passwords and also lets you fill in online forms automatically with your personal information.

A premium upgrade to Passwords that costs $20 per year lets you unlock a PC's screen from a mobile phone and also monitors online accounts for data breaches.

The SafeZone browser installs itself as a separate application. It's based on Google's open-source Chromium browser and includes extra protection for banking and shopping online. SafeZone blocks ads, known malicious websites and third-party browser extensions, checks prices of online shopping items and lets you download streaming videos.

SafeZone's Bank Mode creates a virtual desktop to isolate the browser from other applications, such as hidden keyloggers.

There's also a software updater that scans other software installed on the machine for outdated versions. But it only tells you when it finds something; you'll have to run the updating process yourself.

Avast Free Antivirus comes with a trial version of Avast's SecureLine VPN service, but the free period lasts only a week. After that, you'll have to pay $60 per year.

Rather than making you go to a website to download the software to create a system-rescue disk, this vital recovery tool is built into Avast Free Antivirus. You can copy the self-contained operating system onto a bootable USB flash drive or DVD and use it to revive an otherwise unresponsive system.

Performance and System Impact

Avast Free Antivirus doesn't eat up a lot of system resources, even during active malware scans.

We tested its performance impact on a midrange Asus X555LA laptop running Windows 10 with an Intel Core i3 processor, 6GB of RAM and a 500GB hard drive containing 36GB of files. To measure system performance under various conditions, we noted how long our custom benchmark test took to match 20,000 names and 20,000 addresses on an OpenOffice spreadsheet.

Before Avast Free Antivirus was installed, the OpenOffice test finished in 6 minutes and 56 seconds. After installation, the completion time was only 3 seconds longer, at 6:59. That's a system slowdown of less than 1 percent – not bad.

Avast won't slow your system down too much during active scans, either. The OpenOffice test's completion time during an Avast Full Scan was 7:51, 13 percent slower than the baseline. No other free antivirus program we tested beat that, although Avast's stepsibling AVG came close.

During Avast's SmartScans, which do more than other antivirus products' quick scans, the Open-Office test finished in an average of 7:39, 10 percent longer than the baseline. It was beaten on that score only by Microsoft's built-in Windows Defender software, which inexplicably had a whopping full-scan impact of 58 percent.

The downside of light system impacts is that the scans can take a long time to complete. Avast's Full Scan took an average of 51:32 seconds, about the same as Bitdefender's but half as long as Avira's. Unlike Bitdefender's full scans, Avast's don't get shorter over time.

An Avast SmartScan of the most pressing vulnerabilities took only 2:27 seconds. That was on a par with Defender's quick scan, but about a minute longer than Avira's and Panda's. (Bitdefender Antivirus Free Edition and AVG AntiVirus Free don't have quick scans.)  

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Like most antivirus desktop programs, Avast Free Antivirus' user interface can neither be resized nor run full-screen, but you can move it around on the desktop. The color scheme is dark with brightly colored type. Along the left edge, a navigation column lists major categories: Status, Protection, Privacy and Performance. At the bottom is a link to Settings.

When everything is safe, the Avast main screen's Status shield icon turns green with a checkmark. The shield turns red when you're under attack or need to update things. You can click on the main window to start a SmartScan, but a full or custom scan is three window clicks away.

The major categories in the left-hand navbar have horizontal roll-out elements, putting functions such as creating a Rescue Disk only a click away. On the downside, items reserved for paying customers, such as Firewall and Sandbox, appear grayed out and have small padlock icons next to them.

Avast is the polyglot of the antivirus world with support for 47 languages, including Belorussian and Hindi. There's even a Pirate Talk option for those just in from the bounding main.

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Installation and Support

Avast Free Antivirus' 5.3MB installer file does a quick scan of the system for threats before installing the full application. Be careful — when you click to install the program, you also agree by default to install Google's Chrome browser. You can avoid the latter by unchecking the small box at the bottom of the installation screen.

You'll see a simplified statement that Avast collects personal information as well as web-usage logs for its internal uses. The company says that the data is stripped of identifying information and promises not to sell it. You can opt out of this data collection by digging deeply into the Settings section.

The bottom of the screen teases a "free gift offer" that isn't free – it's a discount on upgrades to paid Avast programs. Yet Avast doesn't bombard you with pop-up upgrade reminders the way some free antivirus programs do.

Although you can set up an account with Avast, you don't need to. From start to finish, the download and installation process took us 6 minutes.

Avast Free Antivirus provides a modicum of support, with technicians available from 8 a.m. to 5 p.m. Central European time (2 a.m. to 11 a.m. Eastern time) weekdays. You can interact with them through online forums and email, but not by phone.

Bottom Line

By including a password manager, hardened browser, game mode and home network scanner, Avast Free Antivirus has gone a step or two further than other free antivirus products. It doesn't require much in the way of system resources, but takes a long time to scan a drive and missed a few malware samples, although neither of those are deal-breakers.

The bare-bones Bitdefender Antivirus Free Edition provides better malware protection, but those wanting a feature-packed antivirus suite for free should seek out Avast AntiVirus Free.

Credit: Brian Nadel/Avast

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  • MartinCook
    The avast antivirus is ok but now more than that...
    i installed it on my computer and i use to scan my directories every weak, the scan shows nothing but still i sometimes get notification which say i have viruses on my computer.
  • shipdog7
    I tried Avast for quite sometime. But got tired of the nagging popups asking to upgrade. I uninstalled and went with Panda Free Antivirus 15.10. So far so good. An occasional popup to let me know an upgrade is available. But does its job silently in the background. I see two files in quarantine.
  • MacOldenly
    I tried avast, and it causes blue screens when I run virtual machines, which is every few minutes. So, I end up having to restart my computer every time I start a virtual machine.
    All stops are at aswVmm.sys+1450a with bug check code 0x00000667. sfc reports no system integrity problems, and uninstalling avast fixed the problem. Reinstalling Avast created the problem again. In the end, I had to leave it uninstalled.
  • tyvek1
    This wanted a credit card immediately for an extra feature was not interested in. Then the uninstall was terrible and even with their utility had to go into the registry and manually remove more. There are a couple others much better with no aggressive directions.