Computer security is a major concern for consumers of late, following the WannaCry ransomware attack that hit huge organisations including the NHS earlier this year, and Petya, a second big ransomware attack. The good news is that if you take steps to keep your machine patched and up to date and install a good security software product you have nothing to worry about.

If you've got a Mac and are wondering whether you need an antivirus, and which Mac antivirus you should choose, you've come to the right place. Here, we reveal the 8 best AV programs for macOS and Mac OS X in 2017.

How we test

For any security software to be effective and worth the install it has to be able to prevent malware from infecting your computer. Mac antivirus is no different. We look for anti-malware properties that prevent known and unknown threats from having their way with your Mac. We use AV-Test.org's own testing data to ascertain the effectiveness of each antivirus in this respect.

But security is only half the story. In order for an antivirus to work effectively it also needs to be unobtrusive. AV-Test also looks at the impact of these pieces of software on your system: in layman's terms, how much the antivirus slows down your Mac, if at all.

For each of the security solutions we outline here, we have tested their ability to keep your Mac safe, and balanced that against the impact on your Mac's performance.

You'll see that even though the best free antivirus programs are good at protection, they tend to hurt your Mac's speed much more than paid-for software. So you need to balance cost against performance impact when selecting a product.

Do Macs need an antivirus?

Plenty of Mac aficionados will tell you that Apple computers are inherently secure and don't require protection. We'd argue that they are wrong - or a bit overconfident, at least.

Macs are generally more secure than their Windows brethren for two reasons. On the technical side, macOS is a Unix-based operating system. As a Unix-based operating system macOS is sandboxed.

It's like having a series of fire doors: even if malware gains access to your Mac, it is unable to spread to the heart of the machine. Macs are not unhackable, but they are more difficult to exploit than Windows PCs.

The second reason is that, right now, there are far fewer Macs than there are Windows PCs. Fewer targets, and these are harder to hack. Is it any wonder that cybercriminals focus on the Windows world?

However, Macs are not entirely safe, and as they grow in popularity and cybercriminals become smarter and greedier, the risk is increasing. Threats such as ransomware are on the rise, and have recently hit huge organisations including the NHS.

WannaCry was big news earlier in 2017, while news broke of Petya - a second ransomware attack - in late June. Also in June, users were warned by security firms Fortinet and AlienVault that there are new variants of malware targeting Macs after being published on the Dark Web.

Cyber security is more important than ever, and a good antivirus is the best place to start if you want to stay safe.

This is one of several in-depth Macworld articles dealing with Mac security. General advice can be found in our Mac security tips; and those who have been hit by a malware attack should try How to remove Mac viruses.

1. Bitdefender Antivirus for Mac

Bitdefender Antivirus for Mac

Our number-one best antivirus for Mac is Bitdefender Antivirus for Mac. In AV-Test's lab (which you can find out more about at the bottom of this article), Bitdefender Antivirus for Mac blocked 100 percent of the threats thrown at it.

Even more impressively, it had a lower than 10 percent system impact, meaning that you won't even know it's protecting you (but believe us, it definitely is). You can read more about Bitdefender Antivirus for Mac here.

UK Mac owners can buy Bitdefender Antivirus for Mac here. There is also a free 30-day trial if you want to try before you buy.

US Mac owners can buy Bitdefender Antivirus for Mac here.

2. ESET Antivirus for Mac

ESET Antivirus for Mac

Another paid-for Mac antivirus: say hello to the excellent ESET. This reasonably priced tool offers 100 percent threat detection, and scores reasonably highly in speed tests. If you'd like to try before you buy, a 30-day trial is available too.

To find out more about ESET Antivirus for Mac, click here.

3. AVG for Mac

AVG for Mac

In AV Test's most recent research, only four of the antivirus packages tested managed to detect 100 percent of the malware thrown at it. AVG is one of those (as are Bitdefender and ESET, numbers one and two in this chart). AVG has a bigger impact on performance than our two front-runners, though, which is why it's down in third place.

There's a free version available with limited capabilities; the Unlimited version, which includes full protection and tuneup, costs £49.99, or $69.99 if you're in the US.

To find out more about AVG for Mac, click here.

4. Norton Security for Mac

Norton Security for Mac

Symantec's Norton Security didn't perform as well in AV Test's recent tests as it did back in December, so we've had to bump it back from its number-two position.

It offered 99.17% detection - which is still great - but when there are three alternatives that scored 100% it makes it more difficult to recommend. It's also not the fastest option available. 

Norton Security retails for £49.99/$69.99 for a single Mac. Step up to £59.99/$89.99 and you can protect up to five devices, which can include Windows PCs and smartphones as well as Macs, which is pretty cool... albeit arguably a little pointless on the smartphone front. You can get further discounts by buying a two-year licence.

To find out more about Norton Security, click here.

5. Kaspersky

Kaspersky

Kaspersky will set you back £39.99/$59.99 a year for the full internet security suite for Macs. In return you get 99.17% percent threat detection from the antivirus, as well as anti-spyware, safer banking software and the rest. Oh, and there is a 30-day trial.

The catch? Greater impact on system performance than some of the better products we list in this story, although not by much.

To find out more about Kaspersky Internet Security for Mac, click here.

6. Sophos Antivirus for Mac

Sophos Antivirus for Mac

Sophos Anti-Virus requires of you only that you cough up some personal details. And even though it costs you nothing, the software detects 99.17% percent of threats.

It does have a minor impact on performance, however. That may be enough for you to notice the difference, depending on what spec machine you have. The paid products above it in our chart are better, but Sophos is a compelling product.

To find out more about Sophos, click here.

7. Avira for Mac

Avira for Mac

Another free antivirus for Mac, and another that successfully protected its test Mac, Avira Free Antivirus 3.2 is in at number seven only because it had more of a system overhead than products above.

According to AV-Test's lab Avira will keep your Mac safe, for free, but you may pay for it in terms of system performance.

To find out more about Avira Free Antivirus, click here.

8. Avast for Mac

Avast for Mac

A Mac security freebie, Avast detects 100 percent of threats. But this tool had a significant performance impact during tests. If you can stand that, it is a good free option. But there are better.

To find out more about Avast Mac Security - Free, click here.