What are the best free anti-viruses for Windows?

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21

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Considered

171

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Aug 21, 2021

Last
Updated

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16 Options Considered

Best free anti-viruses for Windows	Price	Last Updated
84 Bitdefender Antivirus Free Edition	-	Aug 21, 2021
84 Windows Security	-	May 27, 2021
-- Malwarebytes	-	Mar 16, 2021
-- Microsoft Security Essentials	-	Nov 24, 2019
-- Avira Antivirus	-	Oct 3, 2020

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score 27 · Answer 1

Bitdefender Antivirus Free Edition

Top Pro

Excellent results from independent testing labs

Top Con

Often False Alert including website and games from trusted sources (discord, etc)

Top Pro

No commercials

Top Con

Must register to use

Top Pro

Anti-rootkit

Top Con

No customization for advanced users

Top Pro

Extremely unobtrusive

Top Pro

No configurations

Top Pro

Easy to restore and exclude a targeted file, when you don't want it quarantined

Top Pro

Intrusion detection system

Ensures that applications trying to access the Internet or the network are not masked malware. See More

See All

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score 25 · Answer 2

Windows Security

Top Pro

It's free

It's built-in, and is free if running factory installed Windows. See More

Top Con

Doesn't get top ratings in comparisons

Top Pro

No ads

Top Con

Not for beginners

Some advanced virus or malware can pass this antivirus. See More

Top Pro

Part of Windows

Top Con

No way to restore or exclude a file once defender decides to destroy it

Top Pro

It's reliable

It's solid, no-frills, and easy to configure. See More

Top Con

Mediocre ratings in several tests

Slow opening apps while real-time scanning is run. See More

Top Pro

Lightweight

This is made specifically for Windows. See More

Top Con

Harder to set exceptions and restore for false positives

Defender and its options isn't as accessible as other av programs. See More

Top Pro

It's Very Simple

Good protection on Windows 10 Version. Especially for someone who knows about basic security. See More

See All

score 12 · Answer 3

Malwarebytes

Top Pro

Achieved a perfect score in a test performed by AV-TEST

In 2014 AV-TEST tested 7 different cleaning tools (along with 10 antivirus solutions) Malwarebytes was the only tool that was capable of completely removing and restoring the system. It was concluded by AV-TEST to be the best tool for removing malware from infected computers. See More

Top Con

Free version lacks real-time protection

Premium version is required to enable real-time protection. See More

Dr M's Experience

I have been using this av since 2015, And this av is very easy to use. Plus I oftenly install lots of kind of programs in my computer. And sometimes my computer got infected. but this av will always remove the virus successfully... See More

Top Pro

Updated frequently

MalwareBytes has a very strong detection rate and will rarely miss anything. It updates at least daily to stay on top of new threats. See More

Top Con

Doesn't participate in AV-tests

It doesn't participate in AV-test and AV-comparatives. How one can use it without knowing its performance, protection and FA's ? See More

Top Pro

Antimalware

Antivirus is a specific term referring to well-known and established malware, meaning that you'll still remain vulnerable to new and unique malware if you use an antivirus. Malwarebytes is constantly updated to find newer and rarer malware. See More

Top Con

Free version lacks scan scheduling

Premium version of the software is required to schedule scans in advance. See More

Top Pro

Simple setup

Top Pro

Light resource usage

Top Pro

Doesn't ignore adware and toolbars

Malwarebytes removes toolbars that get bundled with software and adware that some other products keep. See More

Top Pro

Free for manual scans

Offers a completely free scan and removal version for personal use. See More

See All

score 9 · Answer 4

Microsoft Security Essentials

Top Con

Used as non-competitive baseline since 2013

All except one tested antivirus scores above Security Essentials. See More

Top Pro

Performance

MSE doesn't seem too resource intensive See More

Top Pro

Simple and Silent

Does the job without distracting you. See More

Top Pro

Less prone to false positives compared to other solutions

Frequent false positives in themselves can reduce security See More

Top Pro

Ease of Use

Top Pro

Accuracy

See All

score 8 · Answer 5

Avira Antivirus

Top Pro

Fast, and free version seems powerful

I've used AVG Free in the past, and it seemed to slow my computer more than Avira does. See More

Top Con

contain bundleware

FantasticPiltzintecuhtli's Experience

It's really good and it gives you extra things like vpn etc See More

Top Pro

Fairly highly rated in tests

Top Con

High Resource Usage

Top Pro

Can install more components if you wish

Optional installs include VPN, System Speedup, a password manager, browser extensions, and a hardened browser. In the case that you've downloaded the Free Suite (not recomended), you can uninstall the above mentioned additional downloads with Avira's Connect app or any uninstaller utility software. This flexibility to cherry pick your extra software keeps the bloatware down somewhat. See More

Top Con

Advertises paid version

Occasional prompts to Upgrade to the paid version. See More

Top Pro

Browser protection

Includes safe search plug-ins for Chrome and Firefox. See More

See All

score 20 · Answer 6

avast!

Top Con

Tries too hard to sell you the paid version

Top Pro

Decent anti-virus protection

InfluentialBrea's Experience

"ui failed to load" message. the avast service is often stopped for unknown reason (check google) See More

Top Con

Too noisy

Avast! has sounds turned on by default. It also has a lot of blinky features of questionable use. See More

Top Con

Makes your system slower than usual

Even though scans are not being run in background, it will slow your system. See More

Top Con

Opt-out installation of Google Chrome

These advertising tactics are simply unacceptable. See More

Top Con

Selling potentially identifying user data

Top Con

Detection rate isn't too solid

Avast! is not the sort of antivirus product to give you peace of mind. In practice, it does miss some malware every now and then. You'll need backup virus protection, which raises the question why you should get Avast in the first place. See More

Top Con

Expires after a year leaving computer exposed to new viruses

Expires and stops updating after a year after which the user's computer may become infected by new viruses not covered by existing patterns. See More

Top Con

May interfere with hyper-V

Since avast has its own virtualization engine, it will cause issues with hyper-V. See More

Top Con

Unable to detect some adware such as FADE adware

Top Con

Blocks or causes issues on apps or games

Top Con

"Smart Screen" feature

When running an unknown application, avast will run it wrapped in a sandbox environment first for scanning, then kill the process and re-run it again. A lot of applications do not like this. See More

See All

score 5 · Answer 7

Ad-Aware Free Antivirus+

Top Pro

Easy to use

Ad Aware Free Antivirus+ has a clean, well designed user interface that's easy to use for anyone. It features a game mode, so that you're not disturbed by any kind of notification or not have your computer's performance weighed down by background scans while gaming. See More

ElatedCihuacoatl's Experience

I tried Kaspersky, Avira, Avast, Bitdefender, AVG (all free). Adaware is on top. See More

Top Pro

Real-time protection

This is one of the few good free antivirus solutions that offer real-time protection, stopping malicious processes on your computer at any given time. Ad-Aware Free Antivirus+ also scans downloads for malware. See More

Top Pro

Solid spyware and virus detection rates

Ad-Aware is a well known veteran in battle against adware and spyware and today still counts as a solid piece of security software on that matter. For virus protection, it gets similar scores as the most trusted paid antivirus solutions without having many false positives. See More

See All

score 6 · Answer 8

AVG Free

Top Con

PC Analyzer always freeze and cannot be closed

Top Con

No Silent mode

Annoying popups cannot be turned off. See More

Top Con

Hard to Uninstall and cause leftover to system

Top Con

No rootkit protection

See All

score 5 · Answer 9

Comodo

Top Pro

Virtual desktop and can run any application at 'containment mode'

Niko Dudnikov's Experience

5-7 years See More

Top Pro

Large set of tools

Antivirus, Firewall, auto-containment, HIPs, Virus Scope, content filter. See More

See All

score 4 · Answer 10

Tencent PC manager

Top Con

Depends upon Bitdefender engine for scanning local files

If you notice its UI, you will find that it uses Bitdefender engine for scanning local files. Sounds like Tencent is nothing but just a clone of Bitdefender. See More

Karan Forever's Experience

I have been using it since last three months. It doesn't make my system slow like other antivirus products do. Not only virus-removing but also registry fixing and other PC issues can be solved by it therefore it is recommended for everyone. See More

Top Con

Slow scanning

It takes too much time to scan full computer. See More

See All

score 5 · Answer 11

Kaspersky Free

Add Video or Image

score 2 · Answer 12

SOPHOS HOME

Top Pro

Free

score 4 · Answer 13

Panda Free Antivirus

Top Pro

Excellent protection

In benchmark tests done by av-test, Panda Antivirus got a perfect score. See More

Top Con

Below average performance

While easy to use and never requiring updates, it does slow down the loading of programs. The rate of slow down ranks it below average performance for launching applications. See More

Top Pro

No more updates

Cloud antivirus means users no longer have to update their system or see dialogue boxes annoying them. Every year or two it prompts you to install major updates to the application, but that's it! See More

Top Con

Popups asking you to buy

When you start your computer you will get a small ad for a moment asking you to upgrade to the paid version, if you are using the free version. See More

Top Pro

Hassle free protection

Runs in the background and silently quarantines viruses with scaring the user. See More

See All

score 2 · Answer 14

360 Total Security

Top Pro

Has multiple scanners

Includes Avira and Bitdefender engines. See More

score 1 · Answer 15

FortiClient 5.0

Top Pro

Best known for it's FortiGate network security appliance

Detects phishing easily, local malware blocking test, etc. Fortinet is best known for its FortiGate network security appliance and other enterprise-level network security products. A local client running on the company's desktops communicates with the FortiGate device for fully managed security. It turns out that this client, FortiClient 5.0, can function on its own as an effective and free antivirus with some interesting bonus features. See More

Answer 16

HijackThis

Add Video or Image

score 4 · Answer 17

Kaspersky Anti-Virus

score 1 · Answer 18

16 Options Considered

My Recommendation for Bitdefender Antivirus Free Edition

My Recommendation for Bitdefender Antivirus Free Edition

Excellent results from independent testing labs

Often False Alert including website and games from trusted sources (discord, etc)

No commercials

Must register to use

Anti-rootkit

No customization for advanced users

Extremely unobtrusive

No configurations

Easy to restore and exclude a targeted file, when you don't want it quarantined

Intrusion detection system

My Recommendation for Windows Security

My Recommendation for Windows Security

It's free

Doesn't get top ratings in comparisons

No ads

Not for beginners

Part of Windows

No way to restore or exclude a file once defender decides to destroy it

It's reliable

Mediocre ratings in several tests

Lightweight

Harder to set exceptions and restore for false positives

It's Very Simple

My Recommendation for Malwarebytes

My Recommendation for Malwarebytes

Achieved a perfect score in a test performed by AV-TEST

Free version lacks real-time protection

Updated frequently

Doesn't participate in AV-tests

Antimalware

Free version lacks scan scheduling

Simple setup

Light resource usage

Doesn't ignore adware and toolbars

Free for manual scans

My Recommendation for Microsoft Security Essentials

My Recommendation for Microsoft Security Essentials

Used as non-competitive baseline since 2013

Performance

Simple and Silent

Less prone to false positives compared to other solutions

Ease of Use

Accuracy

My Recommendation for Avira Antivirus

My Recommendation for Avira Antivirus

Fast, and free version seems powerful

contain bundleware

Fairly highly rated in tests

High Resource Usage

Can install more components if you wish

Advertises paid version

Browser protection

My Recommendation for avast!

My Recommendation for avast!

Tries too hard to sell you the paid version

Decent anti-virus protection

Too noisy

Makes your system slower than usual

Opt-out installation of Google Chrome

Selling potentially identifying user data

Detection rate isn't too solid

Expires after a year leaving computer exposed to new viruses

May interfere with hyper-V

Unable to detect some adware such as FADE adware

Blocks or causes issues on apps or games

"Smart Screen" feature

My Recommendation for Ad-Aware Free Antivirus+

My Recommendation for Ad-Aware Free Antivirus+

Easy to use

Real-time protection

Solid spyware and virus detection rates

My Recommendation for AVG Free

My Recommendation for AVG Free

PC Analyzer always freeze and cannot be closed

No Silent mode

Hard to Uninstall and cause leftover to system

No rootkit protection