The Coway Airmega Mighty looks good in the corner of the room and offers a competitive level of efficiency. It has a HyperCaptive filtration system that captures 99.999% of nano-sized particles — including pet hair and dander.

It has timer settings, an auto mode that adapts to dust levels, and a sensor that switches the machine off when the air is clean. There's also real-time monitoring and colour-coded lights to tell you the pollution levels of the room.

It's designed to work in large rooms — the 109 m² coverage is impressive — but it's even more effective in smaller rooms with a purifying time of just 15 minutes in rooms that measure around 40 m².

Some reviewers have reported having trouble buying replacement filters, though you can find them on Amazon. The machine will actually tell you when it's time to switch the filter, which is handy.

The PhilipsSeries 900 Series is a compact purifier that suits smaller homes, particularly in bedrooms thanks to an ultra quiet Sleep Mode that runs at 20dB and dims the digital display, ensuring an undisturbed night's rest.

It has sensors that automatically assess the air quality 1,000 times per second and adjust the speed of purification. The machine is certified to remove 99.99% of allergens — it tackles dust, pollen, gases, mould spores, bacteria, viruses, and, yes, pet hair — and gives you real-time feedback via the Air+ app.

The app allows you track the air quality and set air purifying schedules around your routine. The device itself has a light system that alerts you to the quality of air in the room at any given time. It also tells you when it's time to change the filter, which is always handy. It's fast working, too, needing just 12 minutes to purify a space of 20m² or 38 minutes to purify a space of 65m².

The Blueair Classic Pro doesn’t come cheap, but it’s a case of premium price for a premium machine. It’s a top-rated purifier that uses advanced technology to purify a wide coverage area of 260m² — ideal for large homes with big rooms — and tackles spaces of 130m² in just 30 minutes.

As far as technology goes, you can monitor air quality on your phone via the Blueair app, with features that include an eco mode, 'welcome home' geo-tracking, scheduling, and air quality feedback. It also uses a medical lighting technology called PhotoPure that "deactivates" bacteria and viruses.

It's made with pet hair and dander in mind, but the HEPASilent filtration technology tackles 99.97% of airborne particles as small as 0.1 microns, including pollen, dust, mould, smoke, and more.

Ultimately, a big and reliable air purifier that does a big, reliable job. If you can afford it, this ranks among the very best air purifiers around.

The Levoit Vital 100S comes from one of the best manufacturers in the field, and makes this list thanks to an energy-efficient pet mode via the Vesync app. It's equipped with a U-shaped air inlet that effectively captures pet hair and captures 99.97% of nasties, including dander, bacteria, and dust.

It automatically detects the air quality and adjusts the purification level accordingly, alerting you to the air quality with a system of lights. Meanwhile, you can control the machine via the app or by using Alexa or Google Assistant — set timers and schedules, or check the filter and air quality index.

Other features include a timer (two, four, and eight hours) plus a choice of four speeds and a 23dB sleep mode. It's also made to cover large areas, which — considering the mid-range price — makes this unit excellent overall value.

You don't buy an air purifier for the aesthetics but the Blueair Blue Pure 511 looks nice in the home thanks to its thoroughly modern, Scandinavian inspired pre-filter cover. Though there's so much more to this purifier than looks.

Made specifically for smaller rooms — purifying spaces of 38 m² space in just 30 minutes — it has a 360° air intake, which means you can place it anywhere in the room and it works just the same. Filtering 99.97% of particles, it takes care of everything you'd expect — pet dander and odours, bacteria and viruses.

At 24dB it's quiet and should be fine in the bedroom overnight, though it's not the quietest option on this list. The real downside is a lack of smart features and connectivity. But if you've need something for a smaller space — or, indeed, if you have just one small pet — it's a good basic choice.