Last updated: May 26, 2026 · 5 min read

Malwarebytes vs Windows Defender: Which Is Better for Your Computer?

What Is Windows Defender?

Windows Defender is the security program that Microsoft includes free with every Windows computer. If you have Windows 10 or Windows 11, it’s already running quietly in the background.

You don’t need to download or install anything. It updates itself automatically whenever you install Windows updates. It scans files as you open them and watches for suspicious activity.

The program used to be called “Windows Defender.” Microsoft now calls it “Microsoft Defender” or “Windows Security.” These names all mean the same thing. Don’t worry about the name change.

According to Microsoft’s official guidance, Windows Defender provides real-time protection against viruses, malware, and spyware without slowing down your computer.

What Is Malwarebytes?

Malwarebytes is a separate security program made by a different company. It’s designed to find threats that other programs might miss.

The company offers a free version that scans your computer only when you tell it to. The paid version costs about $45 per year and runs constantly in the background, just like Windows Defender.

Many computer repair shops use Malwarebytes when they’re cleaning infected computers. It’s especially good at finding sneaky programs that hide on your system and slow it down.

You have to download Malwarebytes from their website and install it yourself. It doesn’t come with Windows.

How Does Their Protection Compare?

Both programs protect your computer, but they work a bit differently.

Windows Defender watches for known viruses and dangerous behavior. It blocks most threats before they can cause problems. It’s designed to be invisible and stay out of your way.

Malwarebytes specializes in finding newer threats and sneaky programs that might slip past other security software. It’s particularly good at catching “potentially unwanted programs” that aren’t quite viruses but slow down your computer.

Independent testing labs check both programs regularly. Windows Defender scores well in most tests. Malwarebytes also performs strongly, especially at finding unwanted toolbars and browser hijackers.

Here’s the truth: no security program catches 100% of threats. The FBI’s Internet Crime Complaint Center reports that adults over 60 lose more to online fraud than any other age group — over $3.4 billion in 2023. Most of these losses happen because people click on convincing scam emails, not because their antivirus failed.

Your own careful behavior matters more than which program you choose.

Do You Need Both Programs?

Good news: you can run both Windows Defender and Malwarebytes at the same time. They don’t fight with each other.

Many security experts recommend this approach. Keep Windows Defender running all the time, then run a Malwarebytes scan once a month as a second opinion.

You can use the free version of Malwarebytes just for occasional scans. You don’t have to buy the paid version unless you want constant protection from both programs.

However, most seniors don’t need both. Windows Defender alone provides solid protection if you also follow basic safety rules like not clicking suspicious email links.

Which One Should You Choose?

For most seniors, Windows Defender is the right choice. Here’s why:

• It’s already protecting your computer right now
• It’s completely free forever
• It updates automatically with no effort from you
• It won’t slow down your computer
• Microsoft supports it and keeps improving it

Consider adding Malwarebytes if:

• You’ve had virus problems in the past few months
• Your computer is running slower than normal
• Strange toolbars or search engines appeared in your browser
• You accidentally clicked on a suspicious link recently
• You want extra peace of mind and don’t mind paying $45 per year

Don’t worry if you’re not sure. You can always add Malwarebytes later if you need it. Windows Defender is protecting you right now.

What Protection Software Won’t Do

This is important to understand: neither Windows Defender nor Malwarebytes can protect you from every online threat.

They can’t stop you from:

• Giving your password to a scammer who calls pretending to be from Microsoft
• Sending money to someone who promises a prize or threatens you
• Clicking “Allow” on a fake virus warning pop-up
• Entering your credit card on a fake shopping website

The Federal Trade Commission warns that scammers increasingly rely on tricking people, not on technical attacks.

Your best protection is staying skeptical. When something feels wrong, it usually is. Close the window and call someone you trust.

How to Check If Windows Defender Is Running

Let’s make sure your free protection is actually working. This takes about one minute.

1. Click the Start button: That’s the Windows icon in the bottom-left corner of your screen.
2. Type “security”: You’ll see “Windows Security” appear in the results. Click on it.
3. Look for green checkmarks: You should see green checkmarks next to “Virus & threat protection” and other items. Green means you’re protected.
4. If you see yellow or red warnings: Click on them and follow the instructions. Usually you just need to click “Turn on” or restart your computer.

Don’t worry if the screen looks slightly different on your computer. Microsoft changes the design sometimes, but green checkmarks always mean good news.

When Should You Ask for Help Instead of Fixing It Yourself?

Sometimes it makes more sense to get professional help rather than troubleshooting on your own. Consider calling for help if:

• Your computer shows red warnings in Windows Security that won’t go away
• Pop-up windows keep appearing even after you close your browser
• Your computer is running very slowly and you suspect a virus
• You’re not sure if a security warning is real or a scam trying to trick you

Our team at The PC Buddy can connect to your computer remotely and check everything for you. We use our virus & malware removal service to clean infected computers every day. You can watch on your screen while we work.

Frequently Asked Questions

Can I use Malwarebytes instead of Windows Defender?

Yes, the paid version of Malwarebytes can replace Windows Defender. But most experts recommend keeping Windows Defender running and adding Malwarebytes on top if you want extra protection. There’s no advantage to turning off the free protection that’s already working.

Is the free version of Malwarebytes good enough?

The free version only scans when you tell it to. It won’t protect you in real-time like Windows Defender does. It’s useful for occasional checkups, but you shouldn’t rely on it as your only protection. Keep Windows Defender running all the time.

Will Malwarebytes slow down my computer?

Malwarebytes uses very few resources and shouldn’t slow down a modern computer. If your computer is already running slowly, the problem is probably a virus or too many programs starting automatically. Malwarebytes might actually help speed things up by removing junk programs.

Do I need to buy antivirus software?

No, you don’t need to buy separate antivirus software. Windows Defender is free and provides good protection. Companies that sell antivirus software sometimes use scare tactics to convince you that you need their product. Save your money unless you have a specific problem.

What if I already paid for Norton or McAfee?

If you already paid for Norton or McAfee, it’s fine to keep using it until your subscription expires. These programs work well too. When it’s time to renew, you can save money by switching to the free Windows Defender instead.

How often should I scan my computer?

Windows Defender scans automatically, so you don’t need to do anything. If you have Malwarebytes free version, run a scan once a month or whenever your computer acts strangely. More scanning isn’t better and won’t make you safer.