Antivirus vs. Windows Defender: What's Best for 2020?

When it comes to protecting your computer against viruses, malware, and other malicious threats, Windows Defender is the obvious choice – mainly because it comes pre-installed with Windows 10 so it’s already there. But is this built-in tool really the best antivirus to offer you the best, all-round protection?

We’ll find out.

Quick List:

A Bit About Windows Defender

You may know Windows Defender as Microsoft Security Essentials if you’re using or have used an operating system earlier than Windows 10. It’s older versions had fewer features and, in fairness, could barely be considered an antivirus. For many years, Microsoft Security Essentials scored at the bottom of most antivirus tests.

However, the new and improved free option that comes with Windows 10 can now:

  • Scan your programs
  • Download new virus definitions through Windows updates
  • Scan automatically or on-demand for malicious programs
  • Offer firewall protection

What do the Tests Say?

In antivirus tests, Windows Defender performs well in the fields of protection, performance, and usability. Its ability to detect and remove threats is comparable to other dedicated antiviruses like Avira and Bitdefender as well.

What it does well

  • It offers 100% protection against zero-day attacks
  • It has 4% web browser slowdown compared to the industry average of 10%
  • It yields fewer false positives than competitors

What it doesn’t do well

That being said, Windows Defender isn’t perfect. In other tests, it didn’t perform as well in “user-dependent” malware attacks.

  • It’s susceptible to user error: While the antivirus will warn you whenever a malicious program attempts to run, it doesn’t stop you from executing it anyway if you choose to do so.
  • It slows down the installation of frequently used applications more than other dedicated antiviruses

Overall, Windows Defender is the basic package, making it an attractive free option for users looking for a barebones antivirus that actually works. It offers decent protection, it’s free with Windows 10, and it runs with relatively low system impact.

The Competition

It wouldn’t be accurate to look at Windows Defender or other antiviruses in isolation. We need to know how Windows Defender performs when compared to some of the biggest antivirus programs out there. We’ve tested Windows Defender against some of the biggest names, such as Avira, Avast, Bitdefender, Malwarebytes and more.

Read on to see how they did…

Avira vs. Windows Defender

Avira vs. Windows Defender

Avira Antivirus (see user reviews) commonly ranks near the top in antivirus testing, outperforming other industry giants like ESET according to AV Comparative. Here’s how it compares with Windows Defender:

What Avira does well:

  • It comes with a password manager
  • Less impact on system performance
  • Avira Protection Cloud to upload unknown samples to the cloud database for analysis (ie. better zero-day protection)
  • Additional browser protection that warns you of risky links before you click them
  • Free Virtual Private Network (VPN)

What Avira doesn’t do well:

  • Avira does not offer a firewall like Windows Defender
  • The free version includes bloatware, such as pop-up advertisements

The bottom line: Avira offers more features than Windows Defender and while it doesn’t come with a firewall, you can upgrade to the premium version for decent all-round protection.

Get Avira Now >>>

Avast vs. Windows DefenderAvast vs. Windows Defender<picture><source type="image/webp" srcset=" 768w, 150w, 300w, 672w"></source><source type="image/jpg" srcset=" 768w, 150w, 300w, 672w"></source><img loading="lazy" class="alignnone size-full wp-image-1342" src="" alt="" width="768" height="403" srcset=" 768w, 150w, 300w, 672w" sizes="(max-width: 768px) 100vw, 768px"></picture>

Avast (see user reviews) is another popular solution that scores high in malware protection, occasionally better than Windows Defender. Let’s take a look at how they compare:

What Avast does well:

  • More features and utility tools
  • Less impact on system performance
  • Gaming mode for disabling background CPU usage and notifications when a game is running
  • Extra features include a home network scanner and a password manager

What Avast doesn’t do well:

  • The user-interface isn’t as easy to use as Windows Defender
  • Slow on-demand scanning – it doesn’t run in the background as smoothly as Windows Defender

The bottom line: Avast comes with more advanced features than Windows Defender, despite both being free. However, because of these features, it does have more of an impact on the performance of your computer.

Get Avast Now >>>

Bitdefender vs. Windows DefenderBitdefender vs. Windows Defender<picture><source type="image/webp" srcset=" 768w, 150w, 300w, 672w"></source><source type="image/jpg" srcset=" 768w, 150w, 300w, 672w"></source><img loading="lazy" class="alignnone size-full wp-image-1252" src="" alt="" width="768" height="403" srcset=" 768w, 150w, 300w, 672w" sizes="(max-width: 768px) 100vw, 768px"></picture>

Bitdefender (see user reviews) is another great antivirus that offers top-of-the-line anti-malware and web protection. Let’s weigh it up alongside Windows Defender:

What Bitdefender does well:

  • Extra features like a password manager and a virtual private network
  • It has a clean and simple user-friendly interface
  • No toolbars or pop-ups

What Bitdefender doesn’t do well:

  • Slow initial scanning
  • The free version is very basic and light on features though

The bottom line: Bitdefender’s free version is comparable to Windows Defender in many cases. Neither one comes with unnecessary bloatware that slows the system down, but if you’re looking to take advantage of the extra features like a free VPN and password manager then Bitdefender is the way to go.

Get Bitdefender Now >>>

Malwarebytes vs. Windows Defender

Malwarebytes vs. Windows Defender

While Malwarebytes (see user reviews) isn’t technically an antivirus, it’s still a fantastic anti-malware program. But how does it compare with Windows Defender?

What Malwarebytes does well:

  • Stops PUPS (potentially unwanted programs) from entering your system BEFORE it has a chance to infect
  • Detects viruses better than most free antiviruses
  • It can work alongside another security software

What Malwarebytes doesn’t do well:

  • Only offers on-demand scanning (no automatic scan)
  • Doesn’t remove threats, only identifies them
  • Many of the best features are locked behind a paywall, but these features are worthwhile

While the free version of Malwarebytes offers on-demand scanning, which is capable of catching some threats better than other antiviruses, it’s weaker than the competition for other types. Plus it cannot remove threats, only detect them.

For this reason, we recommend combining Malwarebytes with another antivirus like Windows Defender to get the best of both worlds. Plus, if you choose to go for the paid version, you’ll enjoy protection against exploits, zero-day attacks, and ransomware.

Get Malwarebytes Now >>>

Other Options

There are plenty of other excellent options like Sophos Home and Trend Micro that have their own feature sets and performance metrics.

Like most people, you probably own multiple devices. Some antiviruses like Panda offer better protection for several devices simultaneously, making them great for families looking for total protection across all devices.

But the question still remains: “Should I bother to get a dedicated antivirus, or is Windows Defender enough for me?”

Here’s What we Recommend

You need to have an antivirus installed on your computer, but you don’t want more than one full antivirus running on your system at a time. Why? Multiple scanners running at the same time can slow down your system and cause conflicts between the antiviruses.

So we recommend using two options:

A combination of Windows Defender (antivirus) and Malwarebytes (anti-malware). Windows Defender functions as your basic antivirus and firewall, while Malwarebytes offers protection against a handful of threats that Windows Defender can’t reach.

Both programs run well together with minimum system impact. Best of all, both are completely free. If you ever believe you need an extra boost, consider investing in the paid version of Malwarebytes for additional anti-ransomware and zero-day attack protection.

And in the case you aren’t a fan of Malwarebytes, you can combine Windows Defender with any of the above options. If you decide to choose another program, simply modify your scanning schedules in order to reduce conflict and to stop untimely scans from popping up.

About the Author

Paul Kane
Paul Kane
Copywriter and editor

About the Author

Writer/editor with a keen interest in cyber security and biotech.
Transparency and Trust – We pride ourselves on being the only site where users can freely contribute and share their reviews on any antivirus with other community members. When you visit an antivirus site we link to, we sometimes get affiliate commissions that support our work. Read more about how we operate.