Free antivirus has genuinely improved. For a lot of people, the protection built into Windows plus one good on-demand scanner is enough to stay safe day to day, without paying a penny. But “free” always comes with trade-offs, and some free products are more about upselling you than protecting you.

Below are the free options I actually trust and use myself. I have only ranked tools I have hands-on tested at Jake Reviews, plus the antivirus already built into Windows. Where a well-known name is missing a score, that is deliberate, I have not tested its free tier closely enough to rate it, and I would rather say so than guess.

The best free antivirus, ranked

1. Microsoft Defender, the free protection you already have

If you are on Windows 10 or 11, you already have a competent free antivirus running: Microsoft Defender. It is built in, switched on by default, and over the last few years it has gone from a punchline to a genuinely solid baseline, scoring well in independent lab tests for core malware detection. It costs nothing extra, uses no second app, and quietly handles real-time scanning, ransomware folder protection and basic web filtering in Edge.

• Free: Yes, fully, and built into Windows.
• Best for: Most everyday users who browse, shop and email carefully.
• Pros: Nothing to install, no nag screens, no upsells, solid core detection.
• Cons: Weaker anti-phishing outside Edge, no VPN or password manager, protection is tied to Windows only.

I do not give Defender a star score here because it is a moving baseline rather than a product I review in isolation, but the honest takeaway is simple: for a careful user, Defender plus good habits is enough, and pairing it with the on-demand scanner below covers most of what it misses.

2. Malwarebytes Free, the best free second opinion (4.3/5)

Malwarebytes Free is the tool I reach for the moment I suspect something has slipped through. It is an on-demand scanner, meaning it does not run in the background in real time on the free tier, but its removal engine is exceptional at cleaning up adware, browser hijackers, potentially unwanted programs and infections that a “full” antivirus left behind. Crucially, it is designed to run alongside your main antivirus without conflict, so it is the perfect free companion to Microsoft Defender.

• Free: Yes, for on-demand scanning and removal. Real-time protection is a paid upgrade.
• Best for: Cleaning an existing infection and as a second-opinion scanner.
• Pros: Outstanding removal, lightweight, no conflict with your main antivirus, dead simple to use.
• Cons: Free version does not protect in real time, no firewall or suite extras.

Read the full Malwarebytes review →

3. Bitdefender, a strong free tier with a clear upgrade path (4.6/5)

Bitdefender is my top overall antivirus pick, and it offers a genuinely usable free tier for Windows that leans on the same top-rated detection engine as the paid product. The free version strips things back to essential real-time protection with very little configuration, which is a feature rather than a flaw if you want set-and-forget cover. My 4.6/5 rating reflects the full Bitdefender product I tested; the free tier is a cut-down slice of it, so treat the score as a measure of the engine quality you are tapping into, not of the free feature set.

• Free: Yes, a basic real-time antivirus tier for Windows. Advanced features are paid.
• Best for: People who want strong, hands-off real-time protection beyond Defender at no cost.
• Pros: Excellent independently verified detection, light on resources, almost no configuration needed.
• Cons: Very few extras on the free tier, no VPN, password manager or anti-phishing suite without paying.

Read the full Bitdefender review →

What about Avast, AVG and the other free names?

You will see Avast, AVG, Avira and Kaspersky at the top of a lot of “best free antivirus” lists. Some of them detect malware well. I am deliberately not scoring or recommending them here because I have not put their current free tiers through the same hands-on testing I apply to the products above, and free antivirus in particular is where the business model matters: historically some free vendors have monetised through aggressive upsells, bundled extras or data practices that are worth reading the fine print on. If and when I test them properly, they will get a scored verdict. Until then, treat them as names to research, not picks I am standing behind.

Free vs paid: what you actually give up

Free antivirus covers the core job, catching and removing known malware. What you give up by not paying is mostly the layers around that core:

Real-time web and phishing protection. Paid suites block malicious and scam sites across every browser. Free cover here is patchier, and phishing is now the most common way people actually get caught.

Bundled extras. A VPN, password manager, identity monitoring and parental controls come with paid suites. If you would pay for even one of those separately, a paid plan can work out cheaper than buying them one by one.

Support and updates. Free tiers usually mean community forums rather than real support, and sometimes slower feature updates.

No nagging. This is the quiet cost of free: most free antivirus tools push you to upgrade with regular pop-ups. Microsoft Defender and the free scan in Malwarebytes are among the least annoying.

Who should just pay

Free is the right call for a lot of people, but not everyone. Consider a paid plan if you:

• Bank, shop or trade online a lot, where strong anti-phishing and safe-banking features earn their keep.
• Want a VPN, password manager or identity monitoring anyway, since an all-in-one suite bundles them cheaply.
• Need to cover a whole family or many devices, including phones and Macs, under one plan.
• Would rather not think about security at all and want proper support if something goes wrong.

If that sounds like you, start with my best antivirus picks. First-year prices are usually low; just note the renewal price before you buy, because that is where paid antivirus gets expensive.

Free antivirus FAQ

Is free antivirus actually safe to use?

The reputable ones are, yes. Microsoft Defender, Malwarebytes Free and Bitdefender’s free tier all do a solid job on core malware. The thing to watch with free antivirus is the business model: read what a free product does with upsells and data before installing lesser-known names.

Is Microsoft Defender enough on its own?

For a careful user, often yes. Defender handles core detection well. I would pair it with the free Malwarebytes scanner as a second opinion, and step up to a paid suite if you want strong anti-phishing or extras like a VPN and password manager.

Can I run free antivirus alongside Windows Defender?

You should not run two real-time antivirus engines at once, as they conflict. The exception is an on-demand scanner like Malwarebytes Free, which is built to sit alongside Defender and only runs when you scan, so it is safe to keep both.

What is the catch with free antivirus?

Usually missing layers rather than hidden danger: weaker web and phishing protection, no bundled VPN or password manager, limited support, and upgrade pop-ups. For many people those gaps are acceptable. For heavy online bankers and shoppers, they are the reason to pay.

Do I still need antivirus if I am careful online?

Good habits cut your risk a lot, but not to zero, and modern threats like phishing and scams target behaviour, not just software. A free baseline like Defender plus the free Malwarebytes scanner is a sensible minimum for anyone, even the careful.

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