How we test bathroom scales
By Oli McKean
Discover how we test bathroom scales to find the Best Buys that consistently give you pinpoint accuracy.
If you’re looking to buy a new set of bathroom scales, you’ll want them to be reliable, to give an exact measurement of your weight and to be easy to use.
Our tough lab tests pick out the ones that consistently give precise and accurate readings - and help you avoid those that are more haphazard and unreliable.
We’ve tested a range of bathroom scales, ranging from around £15 up to £150, which offer body fat analysis on top of the more usual weight measurements to help you find the best model for you and your budget.
Our reviews answer the important bathroom scales questions, including:
- How accurate and reliable are the weight measurements?
- How well do the bathroom scales measure body fat?
- Are the bathroom scales easy to use?
- Should I buy them?
Head straight to our bathroom scales reviews to find the perfect set for you – or read below to discover more about the details of how we test.
How accurate and reliable are the weight readings?
You can’t tell in the shop whether a set of bathroom scales will accurately measure your weight. And even once you’ve bought them it’s tricky to know how precise the readings are. This is where our expert tests come in handy.
We use cast-iron circular weights to make up a range of specified loads to test how accurately each set of bathroom scales measures weight. We also check to see that the bathroom scales repeatedly display the same reading for the same weight so that you can trust them to consistently give you an accurate measurement.
We also look at whether each set of bathroom scales can detect small changes in weight around specified loads so that you’ll be able to see any slight fluctuations in how much you weigh. Five-star rated scales are brilliant at detecting weight changes of 100g, whereas one-star models are much worse here.
Best Buy bathroom scales that earn our recommendation are all among the most accurate and sensitive according to our lab tests.
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How well do the bathroom scales measure body fat?
More and more bathroom scales offer body fat analysis now, and our full bathroom scales reviews reveal how far you can trust this to give you an accurate percentage reading of your body fat.
We measure the body fat of a group of people varying in age, sex and body fat categories using a medical body fat analysis method as a reference measurement. Then each person measures their body fat three times with each set of bathroom scales to see how closely the readings match up.
Are the bathroom scales easy to use?
To help you pick a set of user-friendly bathroom scales, we carry out several ease-of-use tests.
Our expert panel rates how easy it is to weigh yourself with the scales, whether you’ll face any problems when it comes to installing and setting them up for the first time, and whether you’ll find changing the batteries a nuisance, amongst other things. All of these scores combine to generate an overall star rating for ease of use.
Should I buy them?
80%The score that bathroom scales need to earn our Best Buy recommendation
All of the assessments above contribute to making up a total test score, which is the overall percentage figure we give to each set of bathroom scales.
Certain tests are more important than others in determining just how good each set of bathroom scales is, and so carry different weightings. For instance, we think that accurate and reliable weight measurements are more important than how easy the bathroom scales are to use.
The total test score is made up of the following:
- 50% Weighing quality - includes accuracy, consistency and sensitivity
- 30% Accuracy of body fat analysis
- 20% Ease of use
A set of bathroom scales needs to earn 80% in our rigorous tests to be worthy of our Best Buy recommendation. Bathroom scales that score 45% or less are highlighted as Don't Buy scales to avoid.