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Bathroom scales jargon buster

By Haddi Browne

From athlete mode and smart scales to visceral fat and bone density, this guide explains what key bathroom scales terms actually mean.

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The best bathroom scales give you exact and reliable readings, whereas the worst can be inconsistent. Head to how we test bathroom scales to find out more about the lengths we go to, to separate the best from the rest. To find the most accurate body-fat analyser scales, we measure just how accurately each model measures standard weight measurements and body fat. 

Athlete mode

This function is designed to give more accurate readings for regularly active people. Athletic body types are different from standard adult body types because of increased muscle mass and variation in hydration – these differences could distort the body fat reading if measured using a standard Adult mode. If you buy scales with Athlete mode, check the instruction manual to see which mode the manufacturer recommends that you use.



This stands for Bioelectrical Impedance Analysis, which is how body-fat analysers determine your body fat. A small electrical current is passed through the body to calculate your percentage of body fat. It's recommended that those with pacemakers and other internal medical devices do not to use them for this reason.


BMI stands for Body Mass Index. It's a measure adults can use to check they’re a healthy weight for their height. For most adults, an ideal BMI is in the 18.5-24.9 range. Head to our page on calculating your BMI to find out how to calculate yours.


BMR stands for Basal Metabolic Rate. It’s an estimate of the number of calories your body needs to function while resting for 24 hours.

Body-fat analyser / body-fat scales

As the name suggests, body-fat scales are designed to measure body fat as well as weight, to help you differentiate between fat loss and weight loss. We've tested and rated a range of the latest models - you can see which topped our test on our Best Buy bathroom scales page.

Body water

Some body-fat analysers measure your body's water percentage. Body water makes a large contribution to your overall weight.

Bone mass

Some body-fat analysers are claimed to be able to give an indication of your bone density. Poor bone density is often associated with a higher risk of fracture (broken bones) and various nutritional deficiencies, among other things.


Digital scales

Most digital scales are similar to traditional mechanical scales in how they’re designed, in that most basic models just measure your weight in either metric or imperial measurements. Unlike mechanical scales, however, the values are displayed on an electronic screen, which in some models can be easier to read than traditional scales. More advanced digital scales can tell you your body's percentage of fat and water, to help you distinguish between fat loss and muscle loss.


Imperial measurements

Bathroom scales typically let you see your weight in either imperial and metric measurements, or both. Choose imperial units if you prefer to see your weight in stones and pounds.


Maximum weight

This means the maximum weight that the bathroom scales can provide measurements for.

Mechanical scales

Mechanical bathroom scales are designed to do nothing more than the simple job of measuring your weight. They have dial displays, which typically let you see your weight in metric and imperial measurements at the same time.


After a certain number of people have stored their data, some scales are designed to recognise the user and then monitor the difference in weight between each reading for each person.

Metric measurements

Bathroom scales typically let you see your weight in both metric and imperial measurements. Choose metric units if you prefer to see your weight in kilograms.

Muscle mass

Some body-fat scales are claimed to be able to measure your muscle mass – this is the percentage of your body’s composition made up by muscle.


Platform material

What the foot platform of the bathroom scales is made of. Scales with a more robust platform material, such as steel, can be more expensive.



We check whether bathroom scales give consistent readings for the same amount of weight applied. Go to How we test bathroom scales to find out more about our in-depth testing.


Smart bathroom scales

You can connect some bathroom scales to your smartphone or fitness tracker and monitor your progress through an app. Head to our page on smart bathroom scales to find out more about this and whether this is a trend you want to be part of.


Visceral fat

Visceral fat is also known as abdominal fat – it’s the fat inside the abdominal cavity. Some body-fat analysers give measurements for this. A higher amount of visceral fat can increase your risk of several health conditions, such as type 2 diabetes, Alzheimer’s disease and heart disease.


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