Free antivirus applications aren’t what they used to be. Free antivirus companies are now bundling adware, spyware, toolbars, and other junk to make a quick buck.

At one point, free antivirus was just advertising, pushing users to upgrade to the paid products. Now, free antivirus companies are making money through advertising, tracking, and junkware installations.

How They’re Making Money Off Your PC

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Here’s a quick summary of the ways antivirus companies are attempting to make money. It’s similar to how “freeware” applications on Windows attempt to make a buck by loading your computer down with junk.

Changing Your Default Search Engine : Antivirus companies attempt to change your browser’s search engine to one of their own choosing. They then make money when you click ads on these search results pages. This may sometimes be branded something like “secure search,” but you’re actually just using an inferior search engine that makes the company money.

: Antivirus companies attempt to change your browser’s search engine to one of their own choosing. They then make money when you click ads on these search results pages. This may sometimes be branded something like “secure search,” but you’re actually just using an inferior search engine that makes the company money. Changing Your Homepage : Antivirus companies also want to change your homepage, driving traffic to websites that make money by advertising to you.

: Antivirus companies also want to change your homepage, driving traffic to websites that make money by advertising to you. Ask Toolbars and Rebranded Ask Toolbars : Many programs want to install the terrible Ask toolbar. Some companies use a rebranded version of the Ask Toolbar with their own name on it, but one that is still the Ask toolbar.

: Many programs want to install the terrible Ask toolbar. Some companies use a rebranded version of the Ask Toolbar with their own name on it, but one that is still the Ask toolbar. Junkware : Antivirus companies add additional programs (or “offers”) to their installers that are automatically installed by default. They’re paid by the program’s creator if they can install the program on your system — as much as a few bucks per install.

: Antivirus companies add additional programs (or “offers”) to their installers that are automatically installed by default. They’re paid by the program’s creator if they can install the program on your system — as much as a few bucks per install. Tracking: Antivirus companies track your browsing habits and other personal details about you. Some antivirus companies probably sell this data to make more money, too.

Comodo Free

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Comodo tries to change your web browser’s search engine to Yahoo! and bundles the GeekBuddy paid tech support software. It also bundles other Comodo products you might not want, including changing your DNS server settings to Comodo’s servers and installing “Chromodo,” a Chromium-based browser made by Comodo.

As the Comodo-affiliated PrivDog software contained a massive security hole similar to the one Superfish had, there’s a good chance you don’t want a bunch of other Comodo-developed software and services thrown onto your computer.

Ad-Aware Free

Lavasoft’s Ad-Aware pushes “Web Protection” that will “secure your online search” by setting SecureSearch as your web browser’s homepage and default search engine. Despite the name, this isn’t actually a security feature. Instead, it just switches your web browser to use a branded search engine that actually uses Yahoo! in the background — this means it’s powered by Bing.

If you prefer Bing, that’s fine — just use the full Bing website. You’ll have a better experience than using Lavasoft’s rebranded, stripped-down search engine.

Avira Free Antivirus

Avira encourages you to install “Avira SafeSearch Plus.” This is just a rebranded version of the Ask Toolbar, redirecting your search results through a rebranded version of Ask.com’s search engine. if you wouldn’t want the Ask Toolbar installed, you wouldn’t want this rebranded version of it installed either.

ZoneAlarm Free Antivirus + Firewall

ZoneAlarm also wants you to enable “ZoneAlarm Search” as your browser’s default homepage and search engine, along with installing a ZoneAlarm toolbar that is — once again — a rebranded version of the Ask Toolbar.

Panda Free Antivirus

Panda attempts to install their own browser security toolbar as well as change your browser’s search engine to Yahoo, and its home page to “MyStart,” which is powered by Yahoo. To Panda’s credit, they at least don’t attempt to trick you by offering you a renamed Yahoo search engine or home page.

avast! Free

avast!’s installer also tries to install additional software you might not want. We’ve seen Dropbox offered here in the past, but avast! attempted to install the Google Toolbar when we tried installing it.

Programs like the Google Toolbar and Dropbox are high-quality software you might actually want, so avast! comes out looking very good compared to the other options here. But even avast! has done done some questionable things in the past — witness the avast! browser extension inserting itself into your online shopping.

AVG Free

AVG has its own suite of obnoxious utilities, including the AVG Security Toolbar, AVG Rewards, AVG Web TuneUp, and SecureSearch. AVG has to provide instructions for uninstalling these things.

Oddly enough, when we attempted to install AVG Free 2015, it didn’t want to install any of these things on our computer. Because AVG has offered so many toolbars and other similar things in the past, we’re not sure if this marks a change for them or if it’s only temporary. We’re still wary of AVG’s free product.

BitDefender Antivirus Free Edition

BitDefender offers a stripped-down free antivirus. It doesn’t attempt to install any junkware or toolbars on your system, and we’re not aware of any time in the past that BitDefender Free actually bundled toolbars or similar junk. BitDefender is still pursuing the strategy of attempting to upsell you to the paid product.

MalwareBytes Anti-Malware Free

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MalwareBytes doesn’t attempt to install any extra junk on your computer, although the free version doesn’t offer real-time protection. To their credit, MalwareBytes is offering a free tool that’s useful for manual scans — it even picks up and detects much of the adware other programs install — and encouraging you to pay for a more full-featured product.

This tool could be quite useful in combination with another antivirus, like Microsoft’s free Windows Defender or Microsoft Security Essentials solution. But it’s not a standalone free antivirus you can depend on, as it lacks the real-time scanning.

What Antivirus Should You Use?

Even the better antivirus solutions here may be obnoxious. Rather than pushing junkware on you at install-time, they may regularly pop up warnings and other messages, encouraging you to install other software or pay for services. They may be harvesting and selling browsing data and other information, too.

Some antivirus products are legitimately free. Microsoft’s Windows Defender comes with Windows 8, 8.1, and 10. It’s also available as Microsoft Security Essentials for Windows 7. This is a free antivirus product that’s essentially paid for with Windows licensing fees.

BitDefender’s product is currently solid, offering no junk. avast! isn’t perfect and does want you to install additional software, although it is high-quality software. AVG has been full of obnoxious junk on the past but seemed okay when we tried it — we’re not sure what’s going on there, and we’d advise avast! over AVG if you want a free antivirus like these ones.

Paid antivirus are also good options. Kaspersky and BitDefender consistently get better ratings than popular free antivirus applications, so they’re good solutions if you want to pay for something.

Antivirus companies have to make money somehow. Faced with many people who just want free antivirus programs and won’t pay to upgrade, they’ve increasingly turned to advertising revenue, software bundling, tracking, and other questionable practices. Think before you download — even if you download the free version of a legitimate company’s antivirus program, you may end up with junk you don’t want making your computer experience worse.