If you're looking to shield your Windows PC, Mac or Android device from malware, use these tips to help you pick the right protection.
There's no longer any question about using antivirus software. It doesn't matter if you're running Windows, Android or Mac OS X, there's malware out targeting your machine. (There's even malware for iOS now, but no real antivirus software as of yet.)
But what kind of antivirus software should you get? Do 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. And don't forget to check out our top picks for both free and paid antivirus software and apps.
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.
Malware-detection chart, AV-TEST, Windows 8.1, May-June 2015.
Based on testing by the independent labs AV-TEST and AV-Comparatives, Bitdefender and Norton offer the best malware detection among Windows AV products, free or paid, followed closely by Avira and Kaspersky Lab. Among Mac and Android AV makers, those four brands and several others, including Avast, ESET and Trend Micro, routinely lead the pack.
Free AV software offers good protection, but paid provides more features.
Some free antivirus products will protect your machine extremely well from malware. 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 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 and during active 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.
Trend Micro lets you fire up a scan from its start screen.
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 the 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 a month for free. Most Android antivirus apps use a freemium model in which the basics are free, but useful extra features must be paid for.
AVG Antivirus FREE does not include privacy protection or an app locker. CREDIT: dennizn / Shutterstock.
Don't pay for more than what 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 malware just as well as the others. The differences lie in the extra features, such as parental controls or password managers, that each offers. If you don't need what the more expensive products have, stick to the cheaper ones.
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 paid Windows AV software does both; among free products, Avast Free Antivirus, AVG AntiVirus Free and Bitdefender Antivirus Free do.
Don't settle for what 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 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 products are not enough.
Someday, Windows Defender might be as good as third-party antivirus software. But for now, every product we've reviewed — paid or free — does a better job than Windows Defender or its Windows 7 predecessor, Microsoft Security Essentials.
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, OS X and Android devices for a single price.
Bitdefender's Family Pack works with unlimited devices across Windows, Mac and Android.
For example, McAfee's LiveSafe package protects an unlimited number of devices for $90 per year; Bitdefender's Family Pack does the same, but with better malware detection, for $120 per year (currently 50 percent off).
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.
Many iOS apps have "antivirus" in their names, but they really only bundle anti-theft features, URL screeners and call blockers into a single package.
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.