The Best Free Antivirus Protection for 2021: Free Malware, Spyware, and Adware Protection
If you don’t have any antivirus software installed, Windows Defender leaps into the fray, doing its best to protect you. However, its best just isn’t up there with the rest. Microsoft recognizes this fact—when you install another antivirus, Windows Defender goes into hibernation, only emerging if you remove your protection. Still, the idea of getting antivirus without having to pay is attractive. You can upgrade your protection without laying out cash by choosing one of the many free third-party antivirus solutions. We’ve evaluated quite a few free antivirus tools, so you can pick the one that has the features you want.
Your antivirus should definitely have the ability to root out existing malware, but its ongoing task is to prevent ransomware, botnets, Trojans, and other types of nasty programs from getting a foothold. All of the antivirus programs in this collection offer real-time malware protection. Some take the fight upstream, working hard to ensure you never even browse to a malware-hosting site, or get fooled into turning over your credentials to a phishing site.
The Best Antivirus Deals This Week
- Symantec Norton 360 Standard [1 Device, 1 Year] – was £59.99, now £24.99 (£35 off)
- Symantec Norton 360 Deluxe [5 Devices, 1 Year] – was £79.99, now £29.99 (£50 off)
- Bitdefender Total Security 2020 [5 Devices, 1 Year] – was £69.99 , now £34.99 (£40 off)
- Bitdefender Antivirus Plus 2020 [3 Devices, 1 Year] – was £39.99, now £19.99 (£20 off)
Free Antivirus vs. Paid Antivirus
If free antivirus tools are so great, why should anybody pay? For one thing, quite a few of these products are free only for noncommercial use; if you want to protect your business, you have to pony up for the paid edition. At that point, you should probably consider upgrading to a full security suite. After all, it’s your business’s security on the line.
Even for personal use, most for-pay antivirus tools offer more than their free counterparts—sometimes a lot more. For example, ZoneAlarm’s paid edition adds protection against malicious and fraudulent websites that the free version lacks. And Panda reserves quite a few features for paying customers, among them firewall protection, application control, cross-platform support, and detection of insecure Wi-Fi connections.
In addition, many companies don’t offer full-scale tech support for users of the free edition. The first time you need extra help digging a particularly stubborn piece of malware out of your system, you might regret the lack of support.
Independent Antivirus Lab Test Results
Around the world, researchers at independent antivirus testing labs spend their days putting antivirus tools to the test. Some of these labs regularly release public reports on their findings. We follow four such labs closely: AV-Comparatives, AV-Test Institute, SE Labs, and MRG-Effitas. We also take note of whether vendors have contracted for certification by ICSA Labs and West Coast Labs.
Security companies typically pay for the privilege of being included in testing. In return, the labs supply them with detailed reports that can help improve their products. The number of labs that include a particular vendor serves as a measure of significance. In each case, the lab considered the product important enough to test, and the vendor felt the price was worthwhile. The labs don’t necessarily test a vendor’s free product, but most vendors pack full protection into the free product, enhancing premium versions with additional features.
We Test Malware Protection
In addition to carefully perusing results from the independent labs, we also run our own hands-on malware protection test. We expose each antivirus to a collection of malware samples, including a variety of different malware types, and note its reaction. Typically the antivirus will wipe out most of the samples on sight, and detect some of the remaining ones when we try to launch them. We derive a malware blocking score from 0 to 10 points based on how thoroughly the antivirus protects the test system from these samples.
Since we use the same samples month after month, the malware-blocking test definitely doesn’t measure a product’s ability to detect brand-new threats. In a separate test, we attempt to download malware from 100 very new malicious URLs supplied by MRG-Effitas, typically less than a few days old. We note whether the antivirus blocked all access to the URL, wiped out the malicious payload during download, or did nothing. Bitdefender and Trend Micro hold the top score in this test, but Sophos Home Free is close behind.
If you’re interested in learning more about our testing techniques, you’re welcome to read more about how we test security software.
Just about every antivirus product scans files on access to make sure malware can’t launch, and also scans the entire system on demand, or on a schedule you set. Once that cleaning and scheduling is done, blocking all access to malware-hosting URLs is another good way to avoid trouble. Many products extend that protection to also steer users away from fraudulent websites, phishing sites that try to steal login credentials for financial sites and other sensitive sites. A few rate links in search results, flagging any dangerous or iffy ones.
Behavior-based detection, a feature of some antivirus products, is a two-edged sword. On the one hand, it can detect malware that’s never been seen before. On the other hand, if it’s not done right, it can baffle the user with messages about perfectly legitimate programs.
Any antivirus should eliminate spyware along with other types of malware, but some products include features designed specifically for spyware protection. Features like encryption to protect your sensitive data and webcam control to prevent remote peeping typically show up in commercial products, not free ones. But some free products include features like a simple on-screen keyboard to foil keyloggers.
One easy way to keep your PC protected is to install all security updates, both for Windows and for browsers and other popular applications. Windows 10 makes it easier than ever to stay up to date, but there are plenty of security holes in older Windows versions, in popular apps, and in add-ons. Scanning for vulnerabilities in the form of missing updates is a feature most often found in commercial antivirus products, but it does turn up in some free ones. In the chart above you can see which products include these useful features.
What’s Not Here?
This article reports only on free antivirus products that received at least a good rating in our reviews—three stars or better. Microsoft Windows Defender Security Center joined the party with a three-star score not long ago; it’s now at 3.5 stars. Yes, it’s more of a Windows component than a free product. Yes, the very best free antivirus utilities offer many more layers of protection. But Windows Defender protects everyone who can’t be bothered to install a third-party antivirus tool.
Several free utilities devoted entirely to ransomware protection have come on the scene in the last few years. Cybereason RansomFree and Acronis Ransomware Protection, among others, exist for the sole purpose of fending off any ransomware attack that your regular antivirus misses. Bitdefender Anti-Ransomware works by fooling ransomware to think that your computer is already infected. These are useful companion products, but they don’t do the job of a full-scale antivirus utility.
There are also numerous free antivirus utilities that work solely to clean up existing malware infestations. You bring out these cleanup-only tools when you have a nasty malware problem. When the malware’s gone, they have no further use, since they offer no ongoing protection. Our favorite in this category is Malwarebytes Anti-Malware, and it’s definitely one you should try if you’ve got a malware problem. But since they’re free, you can keep trying others if the first one doesn’t do the job. When the scare is over, you’ll need a full-blown antivirus for ongoing protection.
What’s the Best Free Antivirus?
Our current Editors’ Choice for free antivirus utility is Kaspersky Security Cloud Free, which took near-perfect scores in recent tests. Avast Free includes some useful bonus features not found in Kaspersky, including a password manager and a network security scanner. However, due to a problem with sharing of user data between Avast and its subsidiary Jumpshot, we can’t call it an Editors’ Choice at present. If you do have a little cash in your budget for security, the best paid antivirus software does offer more and better protection. If not, try a few of these free tools and see which one you like best.
Worried you might already be infected? Check out our article on the signs you have malware.
Editors’ Note: We are aware of the allegations of Kaspersky Labs’ inappropriate ties to the Russian government. Until we see some actual proof of these allegations, we will treat them as unproven, and continue to recommend Kaspersky’s security products as long as their performance continues to merit our endorsement.
Avast Free Antivirus Review
Pros: Very good scores from independent testing labs and our hands-on tests. Network security inspector. Password manager. Includes browser-independent protection against dangerous URLs. Many useful, security-related bonus features. Free.
Cons: Full protection against dangerous URLs only in Chrome and Firefox. Password manager has limited features and doesn’t require master password. Some bonus features require separate purchase.
Bottom Line: Avast Free Antivirus combines an antivirus engine that scores very well in testing with a surprisingly extensive collection of bonus features.
Kaspersky Security Cloud Free Review
Pros: Perfect or near-perfect scores from four independent testing labs. Perfect score in our phishing protection test. Good scores in our malware-blocking and malicious URL blocking tests. Support for Android and iOS. Free.
Cons: No direct tech support.
Bottom Line: Kaspersky Security Cloud Free offers full-scale malware protection and even some suite-level features. It gets superb scores from the independent labs, and it won’t cost you a penny.
AVG AntiVirus Free Review
Pros: Very good scores in multiple independent lab tests and our own hands-on tests.
Cons: Initial scan slower than average. No longer offers web protection browser extension.
Bottom Line: AVG AntiVirus Free offers precisely the same antivirus protection engine as Avast Free Antivirus, but lacks the impressive collection of bonus features that you get with Avast.
Bitdefender Antivirus Free Edition Review
Pros: Same core antivirus protection as for-pay Bitdefender. Excellent scores from independent testing labs. Good scores in phishing and malicious URL blocking tests. Free.
Cons: Lacks some advanced malware protection layers found in commercial antivirus.
Bottom Line: Bitdefender Antivirus Free Edition includes the same core antivirus technology found in the commercial Bitdefender Antivirus, focusing on the essential task of antivirus protection with minimal add-ons.
Avira Antivirus Review
Pros: Excellent scores from independent testing labs. Good score in our malware blocking test. Free. Option to install many related Avira products.
Cons: Slow on-demand scan. Browser protection only for Chrome and Firefox. So-so antiphishing score. Real-time protection missed some malware EXEs, identified some valid programs as malware.
Bottom Line: The free Avira Antivirus gets excellent ratings from the independent labs, but it doesn’t fare as well in our antiphishing test, and its browser protection only works with Chrome and Firefox.
Microsoft Windows Defender Security Center Review
Pros: Built into Windows 10. Good lab scores. Excellent hands-on malware protection score. Simple ransomware protection. Always on if no other antivirus is present.
Cons: Poor results in phishing protection test. Awkward scan scheduling. SmartScreen Filter works only in Microsoft browsers.
Bottom Line: Microsoft Windows Defender Security Center protects Windows 10 PCs that have no other antivirus protection, and it has significantly improved in lab test results and our own hands-on tests.
Sophos Home Free Review
Pros: Excellent scores from independent labs and in our hands-on tests. Very good scores in our hands-on tests. Decent antiphishing score. Remote management. Free.
Cons: Parental content filter ineffective. Limited to three devices.
Bottom Line: Sophos Home Free gives consumers antivirus protection built for business, including remote management, and it gets great scores in lab tests and our own tests.
adaware antivirus free 12 Review
Pros: Full scan flags safe programs, speeding up subsequent scans. Free.
Cons: Mixed scores in independent lab tests. Low scores in our hands-on tests. No protection against malicious or fraudulent URLs. Lacks features found in competing free products products and in its own previous edition.
Bottom Line: In a complete makeover, adaware antivirus free 12 has a new name and a new look. Under the hood, though, its test results aren’t the best, and competing free products have much more to offer.
Check Point ZoneAlarm Free Antivirus+ Review
Pros: Antivirus protection licensed from Kaspersky. Tough, effective two-way firewall. Free. Bonus features.
Cons: No antivirus lab test results. Lacks some antivirus features. No protection for malicious or fraudulent websites. Behavioral detection tars good and bad programs in testing. Personal data protection fails in testing.
Bottom Line: Check Point ZoneAlarm Free Antivirus+ combines Kaspersky-powered antivirus with an effective firewall, but it lacks protection against malicious and fraudulent websites, and some of its bonus features don’t work.
Qihoo 360 Total Security 8.6 Review
Pros: 360 Connect smartphone app lets you remotely help friends and family use the product. Cleanup, tuneup, vulnerability scan, and many other bonus utilities.
Cons: So-so scores in our malware blocking and malicious URL blocking tests. Dismal score in our antiphishing test. Default configuration not optimized for security.
Bottom Line: The free Qihoo 360 Total Security 8.6 comes with a ton of bonus tools, but its core antivirus protection doesn’t measure up to the best free antivirus tools.