The Best Free Antivirus Software for 2020: Gratis Guardians

By Jacob RoachWriter
— Last Updated:

From browser hijacking to botnets, cybercrime is rampant. To combat it, you need a secure antivirus, which usually comes with a hefty price tag. That’s why we’ve put together a guide to the best free antivirus software on the market.

There’s merit to upgrading, including features and a more sophisticated security infrastructure, but, for this guide, we’re focusing on the five best options you can get for the low price of free. We’re going to talk about everything from features to protection and give you the pros and cons of each option.

Evaluating free antivirus software is different, though. Features that are commonplace for paid software aren’t expected and insistent solicitations to upgrade is unwelcome. Before getting into our list, we’re going to define how we made our choices and give you some thoughts on upgrading to paid counterparts.

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The Best Free Antivirus Software in 2020

Choosing the Best Free Antivirus Software

There are many free antivirus options, but not all of them will make our list. That’s not a matter of list size or overall quality, but of function. Some antiviruses, such as Malwarebytes, don’t protect from threats in real-time. They’re used solely to remove malware already on your machine.

Those options are left out of this list. Our first criterion is that an antivirus scans your machine, but also provides real-time monitoring. Cybersecurity is about prevention, and the free options that scan your machine fall flat on that front.

Obviously, we’re looking at price. The antivirus must be free, not a trial or limited version of the paid software. We are also looking at upgrade paths, though. It’s expected that some features won’t be included with a free offering, so we want to see a logical way to purchase them.

Features matter, but not as much as some other areas. As long as an antivirus provides real-time protection and malware removal, we’re content. Extra features, such as the long list from AVG, get bonus points.

Lastly, we’re looking at protection. We’ll be using the numbers from our antivirus reviews for reference where we tested paid counterparts. Free antiviruses are around 1 to 2 percent less effective, on average. When lab results for a free antivirus are available, though, we’ll make note of it.

Free vs. Paid

There’s a place for free antivirus software. They perform slightly worse than their paid counterparts and often come with a limited feature set, so they’re best when used on a trial basis.

There are a few reasons behind our logic. The first is zero-day malware. Those are attacks that arise the same day an exploit becomes known. Because the malware isn’t in the antivirus’s database, it can’t reference it to know if the software is a threat or not.

Antiviruses use behavior monitoring to address the issue. If software is acting like malware the antivirus has encountered, it’ll flag it for review. Often, the free monitoring system isn’t as sophisticated, leaving you vulnerable to zero-day attacks.

Likewise, you’re getting a rudimentary firewall, fewer protection measures and a shorter list of checks during a scan. It’s dependent on the antivirus and the difference only accounts for a few percentage points in effectiveness, but it’s still there.

Outside of better security, paid antiviruses come with a larger set of features, most notably phishing and ransomware protection. Some antiviruses, such as Kaspersky, have pushed for better webcam protection, too. It was our first choice in our guide on how to secure your webcam.

The better protection scores and larger list of proactive security measures more than justify the price. If you’re a competent web user and regularly monitor what’s on your hard drive, though, a free antivirus will protect you. That said, if you store sensitive data or download a few movies with our best VPN for torrenting, upgrading to a paid antivirus is worth it.

1. AVG Antivirus Free

Editor’s Note 1/28/2020: A report has surfaced showing that Avast and its subsidiaries collect user browsing data from more than 100 million devices. We cannot, in good faith, recommend Avast or AVG products until we look further into the issue. 

AVG is our go-to pick for a free antivirus. It doesn’t do everything exceptionally, but it covers all the bases in a way that few others do. You get a full protection lineup, including multiple scan options, real-time protection and performance scanning.

The basics are AVG’s file and behavior shields. Every file entering your hard drive is scanned, whether it was downloaded from the internet or moved from an external hard drive. Applications on your computer and websites you visit are monitored by the behavior shield for malicious activity.


AVG also includes its web and email shield. The web shield protects against downloads and web attacks that may not require user input. For example, it would block a malicious drive-by download that you didn’t start. The email shield works against phishing, as well as unsafe images and attachments.

AVG calls these “components” and you can customize each. You can turn them on or off and set how they function on your machine. For instance, the file shield gives you options for when a scan occurs, how deep it should go and certain actions that happen when malware shows up.

The scan modes are impressive, too. AVG has six options: basic scan, deep scan, USB scan, file or folder scan, performance scan and boot-time scan. We’re impressed by those options on a paid basis, much less a free one.

It has good lab results, too. AV-Test observed 100 percent blockage of zero-day and widespread malware in its May assessment. AVG had problems with zero-day malware in June, though, blocking only 98.3 percent of samples.

MRG Effitas agrees with those findings, awarding AVG a Level 2 certification in its Q1 full spectrum analysis. When we went through the data in our AVG review, we found that it didn’t allow malware through, it just took time before it was blocked.

As it is an all-around great free antivirus, we recommend AVG. It comes with a free 30-day trial of Internet Security, too, which comes with protection from ransomware, webcam exploits and more.


  • Six scan options
  • Component system
  • Web & email protection


  • Not as secure as other antiviruses
  • Solicitation to upgrade

2. Kaspersky Free Antivirus

Kaspersky doesn’t advertise its free antivirus, but it’s available for download for anyone willing to look. It has what Kaspersky describes as “core protection,” meaning it blocks suspicious websites and common viruses.

In the real world, that translates to using Kaspersky’s cloud database of malware to scan your computer. It provides real-time protection, too, but not behavior monitoring. In most cases, though, that suffices.


The free version of Kaspersky’s software is simple. There are buttons for scanning and database updates on the main screen. Clicking on “more tools” at the bottom reveals more options. You can activate the on-screen keyboard to protect against keyloggers, view your quarantined files and monitor Kaspersky’s database statistics from the menu.

You’ll find many other options, as well, but they are reserved for paying customers. Among the locked features are network monitor and Kaspersky Rescue Disk, which is a way to clean your machine when it’s critically infected.

The settings are where Kaspersky shines in its free offering. You get control over scans with quick, full and targeted options, as well as automatic scans for external devices. You can also configure the different areas of protection, such as the phishing filter.

Kaspersky got excellent marks from the labs we reference. It received a perfect 18 points from AV-Test during its June assessment in protection, performance and usability. It performed better than the industry average in performance tests, meaning it shouldn’t slow down your machine much.

There’s a lot to like in Kaspersky’s paid variant, though, including webcam protection and the network monitor. Still, the free plan is great for what it is, though. You can read our Kaspersky Anti-Virus review to learn about upgrading.


  • Excellent lab results
  • Real-time protection
  • Easy to use


  • Lacks features

3. Bitdefender Antivirus Free Edition

Bitdefender is our first choice for the best antivirus software for many reasons, including its slick interface, excellent protection scores and included password manager, even though it’s not on the level of the best password managers.

The free version doesn’t get that credit, though. It’s great, but not quite as great as the paid counterpart. Even so, it’s able to earn a number three spot on our list for a simple-to-use user interface and the same excellent protection the paid version offers.


It includes scanning and real-time protection against malware known to Bitdefender’s database, as well as behavioral monitoring based on what Bitdefender has encountered. The broad protection will shield against dangers such as ransomware, but the free version doesn’t have features targeted at different threats.

Mainly, you’re missing out on multi-layer ransomware protection. Paid versions of Bitdefender shield specific folders from being accessed by unknown applications. That protects against the nasty file encryption that crypto ransomware aims to accomplish.

Still, there’s a lot to like. Bitdefender Free includes anti-phishing and anti-fraud protection. The phishing protection monitors websites you visit and warns you of potential schemes. Anti-fraud protects you against phishing attempts that aim to redirect you from a legitimate website, which is known as pharming.

Bitdefender’s interface is too simple, though, and that’s why it takes a lower place on our list. You can scan your entire system or drag and drop files to scan them specifically. It’s an easy system that we can appreciate, but there’s not nearly the level of control you get with Kaspersky or AVG.

It has excellent protection scores, as we saw in our Bitdefender Antivirus review. It was 100 percent effective against zero-day malware and widespread malware in AV-Test’s April analysis. The industry average at the time was 99.5 percent.

It also received a Level 1 certification from MRG Effitas in its Q1 2018 full spectrum analysis. Out of the 18 antiviruses tested, only four received that high-level certification, meaning Bitdefender blocked all threats.

Bitdefender Free has some missteps in its options, but it’s difficult to complain without spending a dime. It still has excellent protection and proactive security, with a simple-to-use interface, to boot. It’s a good idea to download it and see if upgrading to a package, such as Total Security, is worth it to you.


  • Easy to use
  • Strong lab results
  • Phishing & fraud filters


  • Lacks features
  • No targeted protection

4. Windows Defender

Windows users are in luck. The popular operating system comes with one of the best free antiviruses pre-installed. Windows Defender includes full system scans, targeted scans and real-time protection on your desktop and browser.

It comes with SmartScreen, too, as long as you’re using Microsoft Edge. That’s where browser-based protection comes from. If you’re using something else, you’re out of luck, but we found Chrome to be the most secure browser available, anyway.


Defender uses cloud-based protection for your device. New malware it encounters is uploaded to the cloud database, which Windows references for its scanning. The database is updated almost every day.

Real-time protection monitors your active processes and uses behavior monitoring to determine if something is malicious. You can turn off real-time protection, but Defender will turn it back on after a short period of time.

If you encounter malware, you can set Defender up to report it to Microsoft. The setting, thankfully, can be turned off and you can submit samples manually. Some samples contain personal information which Defender will ask you about before sending.

It includes ransomware protection, too. The setting is called “controlled folder access.” Instead of adding folders for the antivirus to protect, Defender automatically blocks anything that seems suspicious from modifying your files. You can add exceptions, though.

The ransomware protection seems good, too. Defender blocked all 29 of MRG Effitas’s samples during its Q2 2018 full spectrum analysis. Overall, it was awarded a Level 2 certification, meaning it blocked at least 98 percent of all the samples.

It had issues with potentially unwanted applications and adware, though, missing one of the 20 samples tested. Kaspersky, on the other hand, missed a shocking nine of the samples during the same test. It’s had better results in the past, though.

Unlike many Microsoft services, you aren’t forced to use Defender. If you install another antivirus, it will take over and some of Defender’s features won’t be available. That includes the Microsoft firewall if your antivirus comes with one.

Setups where you want to use a different antivirus, but still want to use the Windows firewall can be difficult to configure.

As an antivirus included with Windows, it’s hard to knock Defender. It’s surprisingly good at blocking malware in real time and comes with decent features, to boot. While not on the scale of other antiviruses, it’s a nice tool if you have nothing else.


  • Included with Windows
  • Ransomware protection
  • Firewall


  • Decent, but not great, lab results

5. Avast Free Antivirus

Editor’s Note 1/28/2020: A report has surfaced showing that Avast and its subsidiaries collect user browsing data from more than 100 million devices. We cannot, in good faith, recommend Avast or AVG products until we look further into the issue. 

Avast acquired AVG in 2016 to the tune of $1.3 billion. They share the same security infrastructure, but maintain different interfaces and features. We like AVG’s interface more, but Avast gets a lot right, too. Its free package has excellent protection scores and a good list of features, to boot.

There are four scan modes, with a custom scan area for configuring your own settings. You get full scans, targeted scans, boot-time scans and, our favorite, smart scans. A smart scan will sweep your computer for malware, performance issues, wireless threats and more. It’s a one-stop shop for PC tuneup.


Each of the scans has its own settings, too, including heuristics and scan areas. You can set the priority of scans, so Avast won’t slow down your machine, as well. It includes a persistent cache that can speed up scan times after your initial scan, so you should see a performance boost after the first use.

If you’re using the included Avast Secure Browser, you can also use the free password manager. It’s not as good as Dashlane (read our Dashlane review), but it’s a surprisingly robust password manager given that it’s free. It can store passwords, notes and credit cards, but you’ll need to upgrade to the paid version to unlock password monitoring.

Avast includes a performance section that will scan your computer for files it doesn’t need. It’s not as good as AVG TuneUp, but that service costs a hefty premium. Again, as a free inclusion, it’s nice to see.

All those features show Avast’s value. It has many options for cleaning your PC, detecting malware and keeping you safe during web use. We like Secure Browser for that reason. It’s a Chromium-based browser that includes a password manager, ad blocker and more by default.

It has rocky lab results, though. AV-Test showed it at only 98.9 percent effective against zero-day malware, below the 99.5 percent industry average, but it was 99.9 percent effective against the AV-Test reference set.

MRG Effitas surprisingly awarded it a Level 1 certification during its Q2 full spectrum analysis. It blocked all malware samples, but it allowed eight out of the 20 PUAs and adware samples that MRG Effitas tested. It seems that failure didn’t factor in to the final certification.

The lab results aren’t horrible, though. Avast has a long list of features that makes it worthy of consideration. You can learn more about the paid version in our Avast Pro review, or sign up yourself with a free account.


  • Lots of features
  • Decent lab results
  • Included password manager


  • Issues with adware
  • Solicitation to upgrade

Final Thoughts

Free antiviruses have an interesting position in the market. They’re a good tool to have to protect against general threats, but they don’t have the power to protect against everything. While options such as Avast and AVG have excellent features, others such as Kaspersky and Bitdefender offer better protection.

Thankfully, all the options are free, so you can download each and find the one you like the most. Be sure to only install one at a time, though, as multiple antiviruses can pose serious compatibility issues.

Which free antivirus are you using? Let us know in the comments below and, as always, thanks for reading.