5 things to look for when buying smart scales 

Simplify your smart scales shopping with our top tips

Shopping for bathroom scales used to be a simpler task. But now, buying smart scales and body composition monitors is harder than ever.

They offer an ever-growing array of readings and measurements, making it tricky to identify which features you need and which ones you don’t. 

As we explained in our best smart scales guide, there are plenty of benefits available if you want to improve your health and fitness. But when it comes to choosing something suitable, the sheer amount of choice can be daunting.

A pair of feet stepping onto a white set of smart scalesCredit: Shutterstock/Koldunov Alexey

We’re in the process of reviewing a range of smart scales here at Exceptional, to help you figure out which ones are worth buying, and which ones… aren’t. 

And for a little extra help, we’ve put together a list of some of the most important factors to consider when you start shopping for your new set of scales.

These tips will help you to narrow your priorities and make choosing the right set of scales a little easier than it otherwise might have been.  


1. Budget

Set a range and stick to it

Prices vary wildly between devices, often reflecting the number of features available. A relatively basic smart scale like the Renpho Elis 1 might cost under £30, while something at the very top end of the body composition and health measuring scale, such as the Withings Body Scan, will set you back almost £400. And there are plenty of others in between these extremes.  

So, when it comes to choosing smart scales, we’d recommend working out what your budget is, and sticking with it. While it may mean you miss out on certain features, the chances are you’ll be able to find something to suit your needs at almost any price point. 

2. Features

How many metrics do you really want?

While setting a budget is obviously important, it’s also worth taking the time to identify what features you might regard as essential.

Do you, for example, just want to know how much you weigh? Or do you want a bit more, such as a breakdown of your body composition, including fat mass, muscle mass, and water mass? Or maybe you want the works, with measures of your heart and nerve health? 

BIA explained

Smart scales work using a method called Bioelectrical Impedance Analysis (BIA). Electrodes in the scales send a small electrical current through your body, and measure how much resistance it encounters. Tissue with high levels of water (such as muscle) offer less resistance than tissues with more insulating properties (such as fat). Smart scale manufacturers then use proprietary algorithms to estimate your body composition. 

Some features aren’t available on all smart scales and body composition monitors. Working out how many features you want, including which features are “nice to haves” or non-negotiables, will go a long way to narrowing down the choices.

If you want to monitor your heart and nerve health, you may need to look at a premium device, such as the Withings Body Comp 

This is also important to bear in mind when it comes to your budget. If you want all the features you can get but don’t want to spend more than £50, then the chances are you will have to compromise, either by giving up some features, or increasing your budget. 

3. Accuracy and consistency

Use smart scales to track your changes over time

To be clear, no smart scale will be as accurate as the gold standard of body composition measurement techniques. Studies have shown that there are quite wide variations between readings from a smart scale, and readings from a medical-grade DEXA scan using X-rays

But that doesn’t mean that smart scales can’t be a valuable addition to support your health goals. 


There is currently no industry body that certifies the accuracy of the claims made by smart-scale manufacturers. As a result, smart scales are usually marketed as ‘wellness’ devices, which don’t require the same level of regulation as medical devices.

Whatever readings you get on these scales can still be used to motivate and support you in reaching your goals, and give you a rough idea of how you are doing over time. But if there’s ever anything you are concerned about, it’s best to see your Dr, rather than relying on the scales. 

Even if some of the body composition measurements may be wide of the mark, you can still find smart scales that are extremely accurate when it comes to your overall weight.

In our reviews, we’ve generally found smart scales to be reasonably consistent in terms of measuring weight. There are some small variations between devices, but usually in the region of 0.2-0.3kg – which, for most people, will not be significant enough to matter.  

This is valuable, because then at least you have a solid baseline to start from. And if your scales can’t give you an accurate weight measurement, then you can’t have any confidence in other metrics it produces.  

If you want to quickly check the accuracy of your scales, try stepping onto the scales with a dumbbell, and then without, and see how closely the difference in weight correlates to the weight of the dumbbell. If you don’t have a dumbbell, even a sealed bag of flour, for example, can do the job. 

When it comes to body composition, the main thing to look for is consistency in readings. Whether they are above or below the real figures, as long as the readings are consistent, then over time, you will see trends developing that you can be reasonably sure reflect what’s actually happening in your body.  

For example, if, over a period, you’re starting to see a reduction in your body fat percentage, while the specific readings may not be perfect, it’s more than likely that the general downward trend is correct. 

Of course, it’s normal for your scales to show day-to-day fluctuations depending on a variety of factors (such as when you last ate, went to the toilet or exercised, for instance) but what you shouldn’t find is enormous swings in the numbers you are getting. 

Person standing on smart scales, using an app to look at their body composition metricsCredit: Shutterstock/Andrey_Popov

4. App support

Some apps are better than others

App support is important to consider when choosing smart scales. All of them will connect to an app, but some are more detailed than others and can offer greater insights into what your scales are recording.  

Some apps, such as Fitbit Premium, will also charge you for additional content. So before committing, check to see whether the information you want to see will be freely available, or whether you might have to pay for it. 

Think about how much data they provide. Some apps will do little more than record the readings from the scales for you. Others will provide a lot more, such as advice on how to achieve your goals, or explanations of the various metrics, and what they mean for your general health.

The level of insight you want from the app may influence which scales you ultimately choose. 

There are other factors to consider as well: how easy is it to understand the data, or use the app? If the app doesn’t present your information clearly, or you feel you are going to get lost in a maze of sub-menus, you may not get the most out of it. 

Finally, if you already use a health tracking app such as Google Fit or Apple Health, then you may want to look for compatible smart scales. Of course, this isn’t mandatory, but if you want the convenience of all your data in the same place, it’s something to consider. 

5. Design and ease of use

Make sure they aren’t going to frustrate you

You may have found smart scales offering everything you want, with a comprehensive app and at a reasonable price point. But if it’s hard to switch them on or change the settings, chances are they’ll rapidly end up collecting dust bunnies. 

The easier smart scales are to use, the more likely you’ll keep using them. Look for things like how easy they are to switch on, whether they feel well made, or if they’re flimsy and feel like they could easily break.

Even consider whether they will be big enough to stand on comfortably. Some, like the Eufy P2 pro, are extremely small. Is it easy for them to take readings, or will you have to stand on them for a long time (probably getting cold in the process)? 

Some smart scales, such as the Garmin Index S2, have buttons on the underside that you need to press if you want to change weight settings, for example. Others will allow you to do this via the app. Working out which way will be easiest for you might be a factor. 

The same principle applies to reading displays. Some will display all the readings on a screen, while others will need you to go into the companion app to get all that information.  

You might also want to consider what kind of batteries are used. Disposable batteries are commonplace and may mean the scales are cheaper up front. But the repeat cost of replacement batteries can add up over time, not to mention the environmental waste it creates.  

Lastly, investigate how easy they are to set up. Some may need you to connect them to a wi-fi network, others use Bluetooth. This will also influence whether the data will transfer automatically (as when using wi-fi) or if you need to open the app before getting on the scales. Many will make this as easy as possible via their apps. But some are easier than others. 


Lots to balance

There’s plenty to weigh up when you’re buying smart scales, and there are plenty of good options out there to suit most budgets.

The factors we’ve mentioned are, in most cases, going to dictate whether a particular set of smart scales is suitable for you or not.

At the very least, this guide will give you a useful starting point to help you work out what matters to you, before you begin shopping.  

Steven Shaw

Written by Steven Shaw he/him


Steven Shaw has been a freelance writer for a variety of outlets, most notably TechRadar. His degree in Medieval History prepared him less adequately for his career than you might expect, but the years spent working in technology focused retail were much more helpful.

Outside of work, Steven is passionate about health and fitness, and particularly enjoys high-intensity interval training, weight training, and increasingly, spending time recovering. Steven loves reading, films and a wide variety of sports. A particular highlight was watching Viv Richards and Sachin Tendulkar batting together in an exhibition match.

He wishes he could travel more. He can also tell you a lot about the Anglo-Saxons, Vikings, and Carolingians. Most of his non-work time is spent with his young children, who are the living embodiment of high-intensity training.