How we test cordless vacuums

Covering everything from how effectively they clean to how much of a racket they make, we've independently tested a range of big-brand cordless vacuum cleaners so you can be sure the one you're buying lives up to its claims.

Our reviews answer the most crucial questions about cordless vacuums:

• Is a cordless vacuum cleaner as good as a conventional vacuum?
• How long will the cordless vacuum cleaner run for?
• How clean will the cordless vac leave my floors?
• Will it be quiet and easy to use?
• Should I buy it?

Find out which models give top-class results in our cordless vacuum reviews.

Watch: What makes a Best Buy cordless vacuum cleaner?

Watch the video below to find out what it takes for a cordless vacuum to earn our coveted Which? Best Buy recommendation, and how a Best Buy could make a real difference to your home.

What are Which? Best Buy, Great Value and Don't Buy cordless vacuums?

Our recommendations will help you narrow down your shortlist, although you should still read our reviews to check for any weaknesses that might impact your buying decision.

Best Buy cordless vacuums

Cordless vacuums that score 77% or more are Best Buys and come with our firm overall recommendation. 

Best Buy cordless vacuums typically excel where it really matters. They're easy to use, effective on different types of floors and keep the allergens locked inside the filters.

Don't Buy cordless vacuums

Cordless vacuums that score 45% or below are Don’t Buy models to avoid.

Don't Buy cordless vacuums typically fall down in some crucial areas. They might be difficult to use, have terrible filters or perform poorly during hard floor and carpet cleaning assessments.

Great Value cordless vacuums

How much buyers are willing to spend on a cordless vac varies, so that’s where our Great Value recommendation comes in. 

These models do pretty well in our tests – scoring 60% or more  – while also being at least 20% cheaper than the average price of the cordless vacuums we’ve tested. 

Great Value cordless vacuums are the ones to go for if you’re looking for a bargain. Some Great Value models also score highly enough to be Best Buys.

Is a cordless vacuum cleaner as good as a conventional vacuum?

In our lab tests, we've found both good and bad cordless and corded vacuum cleaners. One type isn't better or worse than the other. 

We use fine Arizona sand to see how much dust each vacuum cleaner picks up, as well as how much it doesn't hold onto, and would therefore be leaked back into your home.

Our assessments reveal which models lose suction as the battery power decreases – we also run the vacuum cleaners when the battery is only 20% charged.  

How well a vacuum picks up hair and pet fur is important too, so using real cat and dog hair combed into Wilton carpet, we see how long it takes each vac to pick it up. We found one that took more than three minutes, while the best took just 42 seconds.

How long will the cordless vacuum cleaner run for?

There are huge differences in run time between the best and worst models. To measure battery life, we time how long each cordless vacuum takes to charge and how long it can run for.

Many manufacturers base their running time claims on using the cordless vacuum on the standard setting. We make sure that we test each model's running time on its most powerful setting.

To further test the battery, we also check how well the vacuum cleans when only 20% of its charge remains. The best machines will maintain excellent pick-up under these conditions, but some vacuum cleaners pick up much less when the battery begins to run down.

Is the battery replaceable?

Lithium-ion batteries always deplete and eventually die over time, and at Which? we believe that cordless products should last longer than the batteries they come with. That's why we no longer give cordless vacuum cleaners Best Buy recommendations if it's not possible to buy spare batteries from the manufacturer – no matter how good the vac might be.

How clean will the cordless vac leave my floors?

We test the suction of each cordless model on three different surfaces – laminate, floorboards and carpet – so you know whether it will work well in your home.

Using 25g of dust for each vac, we carry out two runs on each surface type, seeing how much of the dust is in the canister at the end.

We also look at the tools it comes with, such as nozzles, to see if they're effective at picking up dust.

Will it be quiet and easy to use?

A vacuum cleaner is no good if it's a pain to use, empty and manoeuvre, so we put each model through a range of ease-of-use tests assessed by an independent panel. We get panel members to rate how smooth and easy it is to vacuum on Wilton carpet, hard floors, stairs, upholstery and uneven surfaces, making a note of how heavy it feels, whether it's uncomfortable to hold and how easy it is to push and turn.

We also ask them to assess how easy it is to take each vacuum out to clean a car, and to vacuum in hard-to-reach places above shoulder height.

If that wasn't enough, we also get them to assess how easy each vac is to assemble and dismantle for storing; what the grip of the handle feels like; how easy it is to empty the canister, change any attachments and read the instructions; as well as what it's like using all the switches.

Finally, we measure in decibels how loud each vacuum is – the worst get up to 88 decibels, which is the same as the noise from a busy road.

Should I buy it?

All the assessments listed above go into making the final overall score for each cordless vacuum cleaner we review. Because we know what matters most to you, some elements are more important than others, so carry different weights:

• 75% suction, filtration and battery
• 20% ease of use
• 5% noise

A model has to score 77% of more to earn our Best Buy recommendation, and any model scoring below 45% is highlighted as a Don't Buy that we think you should avoid.