How we test fridges
By Jess O'Leary
Discover how our tough fridge tests reveal the fridges that cool fast and stay perfectly chilled - to help keep your food fresher for longer.
Only the very best products can be Which? Best Buys. Our video reveals what you can expect from a Best Buy fridge and how the terrible ones just don’t measure up in our tough tests.
We’ve tested the latest fridges on the market to help you choose the best possible chiller for you and your kitchen. Head to our fridge reviews to find out:
- How well will the fridge chill my food?
- Will the fridge keep my food safely chilled?
- Is the fridge energy efficient for the amount of food it can store?
- Can you trust the fridge thermostat?
- Should I buy it?
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How well will the fridge chill my food?
The faster your groceries chill, the longer they’ll last and the more nutrients they will retain. We challenge fridges in our tough tests, to see what they'll be like when you use them at home. That way, you know that a fridge that performs well in our tests will create the best conditions for your groceries and help your food stay fresher for longer.
We set the room temperature to 25°C and part-fill the compartments with gel packs to simulate food already stored inside. We then add a light load of gel packs to the fridge – roughly equivalent in size to what you'd buy when you do a top-up shop for fresh food – and record the time taken for the packs to cool.
The best fridges chill in a matter of hours, whereas the worst struggle to complete our tests during two whole days of testing.
Will the fridge keep my food safely chilled?
We test fridges to check they will keep your food safely chilled 24/7. But room temperatures can vary widely over the course of a day and at different times of the year. So we raise the temperature in our test chamber to 32°C and see whether the gel packs inside remain safely chilled. We then lower the room temperature to a chilly 10°C and recheck the temperature of the gel packs.
How much will the fridge add to your energy bills?
Running a fridge can be pricey – because it’s always switched on you will constantly pay to power it. We measure how much energy each fridge uses to keep cool over 24 hours, as well as how much it uses to chill fresh food. We then calculate what this is likely to add to your energy bill.
To see whether a fridge is cheap to run for its size, we also rate its energy use against the amount of useable storage space it offers.
Our reviews give a more realistic indication of the amount of space you can use for storing groceries. This is because we measure with all of the storage features in place, whereas manufacturers remove all the shelves, drawers and door racks taken out, which makes you think you have more storage space than is actually there.
Without our measurements, you could end up with less room for storing groceries and higher energy bills than you expected.
Check the technical specification tab of each fridge review to compare realistic fridge sizes and running costs.
Our realistic running costs reveal how much you'll pay to power your fridge and chill your food.
Can you trust the fridge thermostat?
When you’re setting up your fridge in your kitchen for the first time, most instruction manuals will recommend a thermostat setting. We test how accurate these are by following the instructions and recording the temperature of gel packs in the fridge.
The best fridges will chill to perfect temperatures as soon as you’ve set them up. But the worst are way off, leaving food too warm. This might make your food go off more quickly than it should – so you’d need to use a fridge thermometer to get the running temperature right.
How easy is it to use and clean the fridge?
Some fridges are easier to use than others, and an irritating niggle can quickly become a major frustration if you experience it several times a day. So we rate aspects such as how sturdy the shelves and drawers are, how smoothly the drawers slide in and out, and whether you can fit a two-litre bottle of Evian water in the door rack.
We also spray cherry juice inside each fridge, let it dry to a sticky mess and then rate how easy it is to clean, to see how likely food and drink spills are to seep into hard-to-reach spots and crevices.
The best fridges are easy to keep clean. The worst have dirt traps that can harbour food spills and nasty bacteria.
Should I buy it?
All of these tests contribute to a fridge's overall Which? test score. However, some tests mean more than others, so here is how each test contributes to the final score. The overall score ignores price and is based on:
- 40% cooling speed
- 15% energy use
- 15% ease of use and cleaning
- 10% accuracy of recommended thermostat setting
- 10% temperature stability in changing room temperatures
- 5% noise
- 5% temperature stability in everyday room temperatures
A fridge needs to score 73% or above to make the grade as a Best Buy.
A fridge needs to score 73% or above in our tough tests to qualify as a Best Buy. Fridges that score 45% or less are highlighted as Don't Buy models to avoid.
Our reviews also reveal our expert verdict on whether we think each fridge is a good buy for its price.
Which? refrigeration testing
We constantly improve our fridge tests to ensure only the very best models are Best Buys. This means that newer models have been tested and rated in a slightly different way to older models - but you can still use the overall test scores to compare one fridge to another.
The section below outlines the key testing changes we’ve made to recent tests. You can see when each fridge was tested under the ‘Technical specification’ tab in each review.
Fridges tested before 2015
Our convenience and cleaning tests were based on visual assessments and an inventory of features.
We also used different methods of calculating running costs, which means these figures can be used as a rough guide to what you’ll pay and shouldn’t be compared. However, running costs don't contribute to the total test score, so this change doesn't influence performance ratings.
Fridges tested between 2015 and 2018
In 2015, we overhauled the way we investigate how easy fridges are to use. Our new convenience test assess how easy the storage features are to use and access, how loud and accurate the alarms are, how good the lighting is inside, and how easy models are to programme.
We also changed our cleaning tests – after Which? members told us that having a fridge that’s easy to clean is the number one priority when it comes to choosing an easy-to-use chiller (based on a survey of 1,092 Which? members in July 2014).
Latest fridge tests - from 2018
We made further improvements to our testing in April 2018. Our ease of use tests now include a test that measures how much force is required to open the fridge door 10 seconds after it has been closed. Some models create such a strong vacuum when the door is closed that opening it again shortly afterwards becomes very difficult.
We've also improved our noise assessment and placed even more emphasis on how a fridge performs when it comes to its essential task of chilling.
Fridge running costs
In light of rising energy costs, we now take into account the amount of power a fridge uses to chill fresh food – to give you a more accurate idea of how each model might impact on your energy bills.
Because our energy calculations are now more accurate, running costs for models tested before and after 2015 shouldn’t be directly compared.
Make sure you avoid a dud and choose a fridge that excels in our tests - check out our Best Buy fridge reviews.
Which? refrigeration fire tests
At Which?, we continually monitor and vary the assessments that underpin our reviews to take account of changing standards and areas of concern.
In September 2017, we called on manufacturers to immediately stop producing refrigeration appliances with flammable plastic backs. Since then, and in the apparent absence of any action from the newly-created Office for Product Safety and Standards (OPSS), we’ve been conducting fire testing on refrigerator backings.
We’ve tested backing samples from more than 80 different refrigeration appliances, across every refrigeration brand that we have on our site. We applied an open flame to each sample and any product that was unable to withstand the flame for 30 seconds has been deemed unsafe and has been made a Don’t Buy.
Hundreds more products have also been made Don’t Buys because the manufacturer either confirmed, or our own research indicated, that the backing on these products was identical to a product we tested and found to be unsafe.
It's important to note that the material used in the backing allows an existing fire to spread – it isn't the cause of the fire itself.
Find out more about fridge safety.