How to buy antivirus software

If you're looking for antivirus software to shield your Windows PC, Mac or Android device from malware, we're here to help you pick the right protection.

There's no longer any question that you should use antivirus software. Whether  you're running Windows, Android or macOS, there's malware out targeting your machine. There's even a little malware for iOS now, but no real iOS antivirus software because Apple doesn't permit it.

But what kind of antivirus software should you get? Will you need to pay for it, or is free software good enough? Is anti-malware software the same as antivirus software? Why are there so many different kinds of antivirus software, even from a single brand? And does using antivirus software pose a risk to computers? 

The answers to all of those questions are complicated, but here are some basic tips to look for while shopping around. Don't forget to check out our picks for the best antivirus software.

• Best antivirus software
• Best Mac antivirus software
• Best Android antivirus apps
• Best internet security suites
• Best free antivirus software

Pick software with a high malware-detection rate

You'll want to make sure the antivirus software stops more than 95 percent of malware, whether it's commonplace malware or brand-new zero-day malware. But make sure that detection rate isn't accompanied by a high rate of false positives, which are benign files mistakenly flagged as malware.

Based on monthly testing by the independent labs AV-TEST and AV-Comparatives, Bitdefender, Kaspersky Lab, Norton and Trend Micro offer the best malware detection among Windows, Mac and Android AV products, free or paid, followed closely by Avast and AVG. The same brands also make the best Mac antivirus software.

Some free antivirus products will protect your machine extremely well from malware, including Kaspersky Security Cloud Free, Bitdefender Antivirus Free Edition and even Microsoft's built-in Windows Defender. 

But the paid products tend to have many more extra features, especially on Windows. For example, Bitdefender Antivirus Plus has built-in ransomware protection, a file shredder, a hardened browser for secure surfing and a password manager.

Just keep in mind that you'll be paying for a yearly subscription to a software license, so factor in paying the same price, or a bit more if you got an introductory discount, again next year.

Look for a light system load

You'll want to read Tom's Guide reviews of antivirus software to see how much each product slows down a machine, both in the background after it's installed and during active malware scans. This is especially important for older, slower PCs that need antivirus software the most. 

See how easy the software is to use

Most antivirus users want a set-it-and-forget-it option, but sometimes it's good to get under the hood and tweak the software to your liking.

For example, Trend Micro lets you start scans right from the home screen, while Avira lets you fine-tune settings most people have never heard of. Again, read our reviews to get a sense of ease of use.

Try before you buy

Most paid antivirus products on Mac and Windows will let you try them out for a month for free. Most of the best Android antivirus apps use a freemium model in which the basics are free, but useful extra features must be paid for.

Don't pay for more than you need

Most antivirus makers sell three or more kinds of Windows products, each more expensive than the last. But each product by a single brand will detect Windows malware just as well as its stablemates. 

The differences lie in the extra features that each product offers, such as parental controls, password managers, backup software, identity protection or online storage. (We also review many stand-alone products that provide such services.) 

If you don't need the extras that the more expensive antivirus packages offer, then stick to the cheaper options.

Look for email and web protection

You'll want antivirus software that automatically screens email attachments before you open them, and also checks websites before you load them. Almost all of the best Windows antivirus software does both; among free products, Avast Free Antivirus, AVG AntiVirus Free and Bitdefender Antivirus Free do. 

Don't settle for the brand that came with your PC

Many new Windows PCs come with one- or three-month trials of well-known antivirus products. But you'll have to start paying for them when the trial period's over. Don't give in — instead, shop around. You might be able to get something better for the same price, or even less.

Microsoft's built-in antivirus software is finally good enough

Over the past few years, we've watched Windows Defender, the antivirus software built into Windows 8.1 and 10, steadily get better and better. It's kind of astonishing how rapidly it's gone from being a sad joke to playing in the top league.

Window Defender is now as good at detecting malware as most, if not all, third-party antivirus software, especially on Windows 10. (That's not quite true of its Windows 7 predecessor, Microsoft Security Essentials.) But you will still get more comprehensive protection against malicious websites and email attachments from third-party antivirus, especially the paid products.

Consider multiplatform, multidevice licenses

If you've decided to pay for antivirus protection and you have a lot of computers and smartphones, check out the bundles that cover several Windows, macOS, Android and even iOS devices for a single price. We've collected our favorites in our list of the best internet security suites.

For example, McAfee LiveSafe protects an unlimited number of devices for $120 per year;  Bitdefender Family Pack does the same, but with slightly better malware detection, for the same price. Both are often discounted.

Anti-malware software is not antivirus software

Malware-removal products, such as Spybot Search & Destroy or Malwarebytes Anti-Malware, are great at cleaning up a system after an infection. But they won't prevent your PC or Mac from becoming infected in the first place. That's what antivirus software is designed to do. 

Don't worry about the firewall

Beginning with Windows Vista, the built-in Windows firewall became just as good as anything the antivirus makers could bundle in. As a result, many antivirus vendors no longer offer their own firewalls.

iOS antivirus software doesn't exist

Some iOS apps have "antivirus" in their names, but they really only bundle anti-theft features, URL screeners and call blockers into a single package. Apple won't let them create true antivirus apps for iOS, and there's not much iOS malware to worry about anyhow. 

Here's a more nuanced explanation of why iOS devices don't need antivirus software.

• Should you still pay for antivirus software?

Shop the best antivirus software and apps

Here are the best antivirus software and apps for the money (in some cases, they are free), including PC, Mac and Android recommendations.