Avast' Free Antivirus costs nothing, but it does an excellent imitation of a security suite, tossing in a password manager, a hardened browser, a gaming mode and a Wi-Fi scanner. It also works with all recent Windows versions and lets you customize the program to suit your computing style.
On the downside, Avast's malware defenses are a rung below the best antivirus software, and you'll have to suffer through long scans and deal with its complicated interface. It also collects and sells your search and browsing history to third parties — although you can opt out to some extent — and shows you ads for other Avast products.
If you want better protection and don't need extra features, our top choices for best free antivirus software, Bitdefender Antivirus Free Edition and Kaspersky Free Antivirus, offer nearly perfect malware detection with little impact on system performance.
What's Covered and Upgrade Options
Avast Free Antivirus works with all Windows releases from Windows XP (with Service Pack 3) to Windows 10.
It's almost a free security suite, what with the extra features we've already mentioned. But if you want a firewall, file encryption or a file shredder, you'll need to upgrade to a paid product.
Avast Internet Security provides a firewall and extra ransomware protection that automatically duplicates key files during an attack. It starts at $60 per year for a single system and goes up to $500 for 10 PCs for three years.
With the Premier edition, which starts at $70 per year, Avast throws in protection against webcam spying as well as a file shredder to make confidential or embarrassing items disappear.
Ultimate is a bundle that packages Premier with an unlimited subscription to Avast's SecureLine VPN service (provided by Avast subsidiary Hide My Ass) as well as its system optimizer and a premium password manager that includes some identity-protection features.
At $120 for a single Windows PC, Ultimate is rather expensive. For the same price, Bitdefender Total Security Family Pack offers unlimited device coverage, including some of the best Mac antivirus software and one of the best Android antivirus apps, with similar features and better malware protection.
Avast's first defensive layer is traditional signature-based scanning that compares files to known malware. The second layer monitors activity and code snippets to look for indications of a malware attack. Finally, anything suspicious gets sent to Avast's cloud lab for analysis, and if it is confirmed as malicious, a new malware signature is sent out to the company's 400 million users.
Avast Free Antivirus includes browser add-ons for Chrome and Firefox that steer you away from dangerous pages. It also scans email attachments for dangerous software.
Avast's malware-detection engine is shared by all Avast Windows antivirus products as well as those of its corporate sibling AVG. The engine does a decent but unspectacular job, according to three of the four testing labs whose results we use.
Our own lab in Utah measures how well antivirus products protect against and block malicious websites, and it gave Avast Free Antivirus a 98 percent rating in tests during the first half of 2018. That matched the ratings of Kaspersky Anti-Virus and beat Avira Free Security Suite, Panda Dome Essential and even AVG AntiVirus Free, though it was a point behind Bitdefender Antivirus Plus.
The AV-Test lab in Germany measures protection against "zero-day" malware that's previously unseen and can't be detected by signature scanning alone, as well as against widespread malware whose signatures are known.
Avast Free Antivirus did well on Windows 7, catching 100 percent of both kinds of malware in January and February 2018, but racked up seven "false positives" — exactly the same as AVG Internet Security.
Avast didn't do as well on Windows 10. In March and April 2018, it stopped only 99.0 and 98.8 percent of zero-day malware, while Avira, Bitdefender and Kaspersky stopped it all. Avast fared better with widespread malware, detecting 100 percent in March and 99.9 percent in April with three false positives.
Another round of Windows 10 tests showed a partial improvement by Avast, as its program detected all zero-day and widespread malware in May 2018, and all widespread malware in June, though it blocked only 99.2 percent of zero-day malware in that month. Avast registered one false positive during both months.
Avast had its ups and downs in tests conducted by Austrian lab AV-Comparatives. Over six monthly tests, its software averaged 99.4 percent detection of online malware, but the actual scores ranged from 100 percent in June to 98.6 percent in March. Avast got 10 false positives over six months. Bitdefender led the way here, with an average detection rate of 99.8 percent, while Windows Defender trailed with 98.4 percent.
But Avast did poorly on tests conducted by Britain's SE Labs, which checks not only detection rates but also how antivirus products treat malware after detection and if they can handle sophisticated attacks that target politicians, journalists and dissidents.
Avast Free Antivirus got an accuracy rating of only 91 percent in SE Labs' early-2018 evaluations. That was behind the ratings of most of the other free antivirus brands. Avast failed to spot five out of 100 attacks, and couldn't stop four more, leading to nine infections overall.
Even AVG did better, tying Avira at 94 percent. Kaspersky led the free pack with 99 percent.
Security and Privacy Features
Avast's SafeZone secure browser, part of Free Antivirus, can keep your wallet secure by limiting add-ons while blocking ads and suspicious sites. Its Bank Mode isolates the browser from the rest of the system to thwart nosy malware.
The password manager stores an unlimited number of credentials locally; it works with Firefox, Chrome and Avast's SafeZone browser.
The Wi-Fi Inspector scans your local network for flaws such as weak passwords, incorrect settings or outdated firmware. There's a seven-day unlimited-data trial of Avast's SecureLine VPN service, but after that, SecureLine costs $20 a year for a smartphone, $60 a year for a PC or Mac, or $80 for five varied devices. By contrast, Panda Free Antivirus gives you 150MB of free VPN data a day.
Should your PC get bogged down with malware, Avast's Rescue Disk software can help. Just load the software onto a CD or USB drive and restart the system.
Performance and System Impact
Avast's Free Antivirus tended to use too many of our system's resources during active scans, which took a long time.
To check system performance, we used our custom benchmark test, which times how long it takes the CPU to match 20,000 names and 20,000 addresses in an OpenOffice spreadsheet. Our testbed was an Asus X555LA notebook with a 2GHz Core i3 processor, 6GB of RAM and 117GB of files on a 500GB hard drive, running Windows 10 with the latest updates.
Before we installed Avast Free Antivirus, we established a baseline of an average of 6 minutes and 54 seconds to finish the OpenOffice benchmark. Completion time rose to an average of 7:21 with the Avast software loaded, but without any active scanning taking place, indicating a 6.5 percent passive decline in performance.
That's a little worse than AVG and Bitdefender's 5 percent declines, but better than Panda and especially Avira, whose 9.8 percent hit brought up the rear. Kaspersky was the champion, slowing the Asus by only 2.6 percent.
During Avast's full scan, the OpenOffice completion time stretched to 8:47, 27 percent slower than the baseline and 19 percent slower than Avast's background load. Only Avira Free Antivirus did worse, with a full-scan slowdown of a whopping 35 percent. AVG AntiVirus Free was the overall winner, slowing down the system by only 11 percent.
Smart Scan, Avast's term for a quick scan, put less stress on the system, letting the OpenOffice task finish in 8:24, 22 percent slower than the baseline and 14 percent slower than without an active scan. But that system mpact was still heavier than all except Avira. AVG and Panda tied for best with quick-scan impacts of 7.4 percent.
Avast Free Antivirus took an average of 1 hour and 42 minutes to look at 795,601 files on our Asus. That wasn't as long as Bitdefender's initial 2-hour-and-15-minute scan, but Avast's scan times didn't decline with subsequent runs.
Avast's main interface window has the standard green check mark next to the words "You're Protected." If something's amiss, the check mark changes to a red X.
There's a button to start a Smart Scan, which checks for malware, weak passwords and vulnerable software as well as network and performance problems. Three clicks away are the Protection settings, which let you start a full scan, scan specific folders or run a boot-up or custom scan. You can scan any single item by right-clicking it in Windows Explorer. You can schedule scans to run daily, weekly or monthly.
Avast's interface is both complex and customizable. You can turn off or adjust just about every tool, from web shields to Browser Cleanup. The more you dig, the more opportunities there are for personalization.
If the program becomes too intrusive, you can adjust the aggressiveness of the scanning or try Avast's Game Mode. Avast's Task Tray icon lets you update the software, temporarily disable protection, peek into the quarantine area or switch to the secure browser.
Installation and Support
Installing Avast Free Antivirus took a little over 7 minutes. We got to choose from 48 languages, including Pirate Talk; whether to make SafeZone our default browser; and whether to install the Avast app on an Android device.
You can't opt out of this during installation, but you can at the bottom of the Settings Privacy section. While there, you might want to turn off Avast's pop-up ads as well; you'll still get ads for upgrades on the program's main page, though. You'll find more information and more ways to opt out at Avast's Privacy Portal.
There's no need to set up an online Avast account, but if you do, you can remotely control some aspects of the company's mobile apps and also use the Privacy Portal.
Avast Free Antivirus' users get neither phone nor email support. You'll need to check the company's forums, FAQs, installation tips and knowledge base to fix any problem.
Avast Free Antivirus offers more features than other free AV products and comes close to a full security suite. Its protection is OK, but it's a step behind the best. In addition, Avast's program can slow the system a bit more than necessary, and its privacy policies leave something to be desired.
Credit: Tom's Guide