If you're looking for a set of digital bathroom smart scales we've tested the best scales that sirelessly sync with your smartphone.

Everyone’s getting fitness trackers, walking more than 10,000 steps a day, donning the trainers and setting out on a jog recommended by RunKeeper or another of the many exercise apps. See: Best Fitness Tracker

Exercising to get fit is a noble aim for us all. Even if you don’t live longer – which you are more likely to do – you should live better as you get older.

But for many of us exercise is as much about weight loss as it is general fitness. All those Fitbit steps go hand in hand with the 5:2 Diet or some other fashionable eating regime – because we realise we’re overweight and need to shed a few kilos. You need to look for the best scales that will help you maintain a healthy weight and look at otherhealth metrics.

A fitness tracker can tell you how many steps you’ve taken and even take a decent guess at the number of calories you’ve burnt in the process but it can’t measure your weight.

A standard set of step-on scales will do the trick, but in today’s world of the quantifiable self we appreciate all our data to be digitally collated and presented to us in attractive graphs and charts.

For this we need a set of smart scales – digital weight-measuring devices that sync with a smartphone app, and keep us fully aware of how much we weigh.

Without a set of smart scales you have to enter your weight into other apps manually each time. Wireless syncing of weight and other health metrics takes away all that bother, and over time builds up a trend analysis of your weight (be it loss or gain).

Best Scales reviews: Why is weight important for health?

Being overweight or obese can increase your risk of health problems such as heart disease, stroke, type 2 diabetes, high blood pressure (hypertension), kidney disease and some forms of cancer.

Note that being underweight also incurs possible health risks, such as brittle bones (osteoporosis), and iron deficiency (anaemia).

Recent studies indicate that we need fewer calories than our parents, due to an increasingly sedentary lifestyle. Cutting down on unnecessary calories is an obvious start, but the benefits of getting more exercise into your life are even greater for your health and general wellbeing.

Best Scales: not just weighing machines

Smart scales measure a lot more than our weight. A decent set should also inform us of our Body Mass Index (BMI), lean mass and body fat percentage. These metrics help us understand what our own best weight should be, as it depends on your height as much as your actual weight in kilos or stones.

(When measuring the various health stats remember that these averages are just that, and an indiividual’s best ranges may differ depending on various factors. If in doubt discuss these with your doctor.)

Best Scales reviews: What is BMI?

Body Mass Index (or BMI) is a measure that shows if you are a healthy weight for your height. 14 stone (89kg) might be an unhealthy weight for someone of average height (men: 5ft 9in or 175.3cm; women: 5ft 3in or 161.6cm), but perfectly acceptable for a 6ft 5in man.

Doctors suggest that an ideal BMI for adults is in the range 18.5 to 24.9.

25-29.9 is overweight; 30-39.9 is obese; and over 40 is very obese. Less than 18.5 is underweight.

Note that the term ‘obese’ is not a description of what you look like but a clinical term to describe your increased health risks.

(BMI is interpreted differently for children.)

BMI is not always a great indicator of health, because it does not take into account body composition – whether or not that excess weight is muscle or fat. Because muscle is denser than fat many physically fit adults and even athletes are mistakenly classified as overweight by the BMI measurement.

That said, BMI is a pretty good health-risk indicator for most people.

Best Scales reviews: What is body fat percentage?

Body fat percentage is the portion of your body made up of fat cells.

For men aged 20 to 40, 10-20 percent body fat is considered healthy. For older men the range 19-23 percent is good.

For women aged 20 to 40, 19-26 percent body fat is healthy. For older women 23-30 percent is good.

If you're after a device that measures body fat and muscle quality that isn't a scale, then there are products out there like the Skulpt Chisel scanner. It's the size of a smartphone and very easy to use - it measures how much high frequency current flows through your muscles, thereby determining how lean certain muscles are. Click here to view the Skulpt Chisel.

How do smart scales measure body fat, muscle and water?

Smart scales measure body fat percentage by using a body impedance method, or Bioelectrical Impedence Analysis (BIA).

For example, the Fitbit Aria has four sets of ITO electrodes that shoot a small 180 micro amp current up one leg and down other to measure body impedance. The iHealth Core also uses four electrodes but at 100 micro amp. Of course, the current is pain free and harmless – although if you have an internal electronic medical device such as a pacemaker, you should consult a doctor before using such scales. In that case, look for the smart scales that measure just weight and BMI.

Electrical impedance is the measure of the opposition that a circuit presents to a current when a voltage is applied. The electrical current flows easily through muscle, which has a high fluid content, but less easily through fat. By measuring your body’s impedence (that is, its resistance to the current) the quantity of muscle is determined. From this, the quantity of water and fat are estimated.

Because this measurement can be subjective, the body fat reading may not match other scales or the results of manual methods such as calipers.

You might get more accurate body fat readings after a shower and light foot towelling as the humidity on feet makes for better contact.

You won’t get any reading if you’re wearing socks or shoes!

Best Scales reviews: What is lean mass?

Lean mass is a measure of muscle, organs, bones and water, rather than essential or storage fat. Having a high percentage of lean mass boosts your metabolism, making it easier to maintain an overall healthy weight. It can also help reduce inflammation.

Measuring Lean Mass is another way of determining “good” and “bad” excess weight, and is the other side of body fat percentage.

A healthy body fat percentage is between 15 and 20 percent for men, and 20 and 25 percent for women. The remaining percentage is made up of lean mass, meaning that a healthy lean mass percentage for men is 80 to 85 percent for men and 75 and 80 percent for women.

Best Scales: Other health metrics

Other metrics measured by some smart scales include:

Visceral fat – this is fat that exists around your vital organs, and is one of the main risks to long-term health. This is measured by the iHealth Core and Salter Curve Analyser Pro.

Body Water Percentage – the rate of water in body composition. This is measured by the iHealth Core, Withings Body Cardio, QardioBase, Salter Curve Analyser Pro, and Koogeek Smart Health Scale. Aim for a body water percentage just over 50 percent. It depends on age as well but men should try to get to a total body water percentage between 50 and 65 percent. The ideal range for women is between 45 and 60 percent. Drinking more water, and eat more fruit and vegetables to improve your body water percentage.

Bone Mass – bone density is an important health metric because, like muscle, bone is a living tissue that can become stronger with exercise, as well as a healthy diet (calcium and vitamin D). For most people bone mass starts to reduce after the age of 40, and regular exercise can prevent this loss. This is measured by the iHealth Core, Withings Body Cardio,QardioBase, Salter Curve Analyser Pro, and Koogeek Smart Health Scale.

Pulse Wave Velocity – PWV measures the elasticity of the aorta arterial wall, and so arterial stiffness. High speed (v= 9.2m/s) indicates risky high blood pressure and stiff arteries. Low blood pressure and soft arteries result in low speed waves (v= 5.3m/s). Body Cardio measures the time difference between blood ejection by the heart in the aorta and the arrival of the blood flow in the feet. The time it takes for the pressure wave to travel along the arterial tree is called the Pulse Transit Time. You can improve your PWV through lifestyle changes: losing weight, exercising more, and limiting salt and alcohol intake. Only the Withings Body Cardio measures PWV.

Basal Metabolic Rate (BMR) – an estimation of the energy (measured in calories) expended by the body at rest to maintain normal body functions (heart beating, respiration, maintenance of body temperature, etc). This is measured by the Koogeek Smart Health Scale and Salter Curve Analyser Pro..

Best Scales: multiple accounts

All of the scales reviewed here allow for more than one person to sync their data with the relevant app. This is great if the whole family or flat share want to use the scales. The scales take a good guess at who is standing on them based on previous weight, and this general works well. The only problem can be if some people’s weight is very similar to anothers, which will confuse the scales.

Best Scales: positioning the scales

Where you place your scales is important, as you’ll get different readings (sometimes out by a few kg or pounds) depending on where it is on the floor. Put it on a flat, hard surface (bathroom tiles work well) if you can, and not on carpet, which will trick the scales into understating your weight. Some of the scales (for example, the Salter Body Analyser Scale) can be adapted for use on carpet.

And try to position the scales in exactly the same place each measurement – another reason why tiles (with their straight lines) are a good choice.

It’s still fine to use the scales on carpet as long as you measure yourself the same way each time.

Best Scales: when to weigh yourself

Your weight and body fat percentage (and therefore other metrics) will change throughout the day so it makes sense to weigh yourself at the same time each day. You should be at your lightest as soon as you wake up.

Best Scales: Wi-Fi or Bluetooth

Some of the scales tested here can connect wirelessly with its mobile app via both your home's Wi-Fi and/or Bluetooth. Others just connect via Bluetooth. The advantage of Wi-Fi is that you don't need to have your smartphone amywhere near the scales when you step on, as you would with Bluetooth-only scales.

That said, most of us are rarely out of range of our smartphones, and connecting via Bluetooth ensures ach user registered to the scales gets his or her own weight recorded. Over Wi-Fi the scales (accurately in our tests) guess who you are deoending on recent weight measurements.

Best Scales Reviews: testing the best

Now let's take a look at the range of smart scales available today and tested in our labs (ok, our bathrooms).

Withings Body Cardio

Withings Body Cardio
  • Rating: ratingsratingsratingsratingsratings

 Price: Body Cardio – £139.95, US$179.95; Body – £99.95, $129.95.

Body Cardio measures: weight, BMI, body composition (fat, muscle, water & bone mass), standing heart rate and Pulse Wave Velocity (PWV)

Body measures: weight, fat mass, muscle mass, bone mass, and water weight.

Users: 8

Colours: White and Black.

Withings was one of the first manufacturers of smart scales, and the latest, the Body Cardio, offers a wide range of health measurements. It also offers a lite-version, the Body. Buy direct from Withings or from Amazon. Make sure you are buying the right Withings scales when looking at the best online prices: either the basic Body scales or the more sophisticated Body Cardio scales.

The entry-level Body scales are available from Amazon UK and Amazon.com in the US.

The top-end Body Cardio scales are available from Amazon UK and Amazon.com in the US.

Both scales sync well with the Withings range of activity trackers, such as the inexpensive Withings Go and the waterproof Withings Activité, which looks like a normal analogue watch but measures basic activity data. See our round up of the best waterproof activity fitness trackers.

Unlike the other scales the Withings scales display your previous day’s step count and even a trend graph right there on the scale display. When the Body Cardio scale is connected over WiFi it even provides a daily local weather forecast – handy for joggers and outside exercisers. If you don't use a Withings activity tracker you can sync your phone's step counter to the Withings Health Mate app.

What is Pulse Wave Velocity? The Body Cardio monitors something none of the other smart scales offer. Pulse Wave Velocity (PWV) is a measurement that is a key indicator of cardiac health and associated with hypertension and risks of cardiovascular incidents. PWV is defined as the speed at which heartbeat-generated vibrations spread out along the arterial wall. A high PWV indicates stiff arteries or high blood pressure.

Body Cardio connects to the free Withings Health Mate app (iOS and Android) and automatically syncs data after every use of the scale. Graphs help users visualize trends over time and note how their weight impacts overall health. After a few weeks, users should be able to see how their lifestyle impacts their PWV.

The app's home screen is clear and concise, showing you your health stats in one easy glance, including  steps either from your Withings activity tracker or from your phone's step counter.

Withings Body Cardio app

Users can set goals, earn rewards over time and celebrate health milestones. Health Mate also offers integration with 150 partner apps to provide nutrition tracking, GPS run tracking and more to make it an integrated health aid. All Body Cardio data stored in the Health Mate app integrates with the Apple Health app.

Our one complaint about the Withings scales is the graphs on the app. When you go into more detail some of the graphs turn into quite confusing squiggles, where a simple trend line would have sufficed.

Body Cardio features a rechargeable battery rather than running on four AA batteries like the other scales tested here. Withings claims that this should last a year.

Verdict: The Withings Body Cardio does pretty much everything a smart scale can, including even cardiovascular health measurements. It syncs with Withings range of activity trackers for all-round fitness monitoring, and can use a phone's basic step counter if you don't own a tracker. The Body Cardio is our favourite smart scale. It's pricier than the others but offers just about everything you might possibly need. Our only complaint is the squiggly graphs on the mobile app.

Body Cardio specs: 35cm x 35cm square, by 2.85cm height. Body Cardio syncs via: Bluetooth and Wi-Fi

Body specs: 35cm x 35cm square, by 2.85cm height. Body syncs via: Bluetooth and Wi-Fi

Qardio QardioBase

Qardio QardioBase
  • Rating: ratingsratingsratingsratingsratings

Price: £129.99/US$149.99/€149

QardioBase measures: weight, BMI, body composition (fat, muscle, water & bone mass)

Users: 8

Colours: White

One of our favourite wireless internet scales is the circular QuardioBase Smart Scale from Qardio. It looks great, gives very fast readings, includes most health metrics, and has a clear, simple app.

The QardioBase measures weight, BMI, and full body composition (body fat %, muscle, water and bone mass). It doesn’t measure heart rate like the Withings Body Cardio, but the better activity trackers will do this for you anyway.

It can connect to the smartphone app (Android, iOS, Kindle) via Bluetooth and Wi-Fi (2.4GHz), and the simple setup is completed using the app. Users with visual impairments will appreciate the fact that the app has full voice functionality.

The app is clear and simple to use. We preferred its historical data graphs to the slightly confusing Withings charts. It beats the Fitbit Aria scale with its full body-composition measurements, but Fitbit tracker users would need to manually input the weight readings to their app.

QardioBase app

This scale will give you encouraging smileys when you’re progressing towards your weight goal, and can even give haptic feedback – gentle vibrations that let you know your weight has been taken and stored in the app.

QardioBase is compatible with Apple Health and Apple Watch, and integrates with Google Fit and S Health.

Up to eight people can be set up with each scale, and each is private.

There is a special Pregnancy Mode so expectant mothers can track their progress and even add photos to each measurement. There’s also a cutback mode that is best for people with implanted devices such as pacemakers.

We did find the scale a bit wobbly at first (probably caused by the stylish but less-stable circular design – Qardio may be guilty of form over function here), but four extra feet are included so you can customise to your floor. It works on carpet, but – as with all scales – is best on a flat and hard surface when you weigh yourself.

This digital scale requires 8 AA batteries, which should keep the scale going for a year.

It comes with a generous three-year warranty and a 60-day money-back guarantee. You can buy direct from Qardio or from online retailers such as Amazon, where you might find some discounts. At the time of writing Qardio was offering a 10% discount from its store.

Look at the best prices from Amazon UK or Amazon.com.

Fitbit Aria

Fitbit Aria
  • Rating: ratingsratingsratingsratingsratings

Price: £99.99, US$129.95

Measures: Weight, BMI, Lean Mass, Body Fat Percentage.

Users: 8

Colours: White and Black.

The most popular activity trackers are made by Fitbit (see our Which Fitbit is best? feature for full details of its range), and the company has a set of smart scales that wirelessly sync with its mobile app and desktop dashboard tools.

See also: Fitbit Zip, Fitbit One, Fitbit Flex, Fitbit ChargeFitbit Charge HR, Fitbit Alta, Fitbit Blaze and Fitbit Surge

Like most of the smart scales reviewed here the Fitbit Aria is powered by four AA batteries.

The Aria is stylish, available in chic black or white, and topped by 0.3 inches of glass.

As soon as you step on the Aria it starts measuring your weight and calculating BMI etc through knowing your height and other personal statistics via your Fitbit account.

Fitbit Aria scales app

It then identifies you and displays your weight and body fat percentage. You can set up the Aria to recognise up to eight individual users, so it works for even the largest families. Everyone’s data is private, and available only by their own Fitbit accounts.

The app's interface is clear and can show data in attractive graphs. Setting goals for individual metrics is also simple.

You don’t need to be a Fitbit tracker user to own the Aria scales, but it makes a lot of sense as the data sync is so good, and exercise monitoring is one of the best ways to help you get to and maintain a healthy weight, BMI and Body fat Percentage it has the major metrics you'll look at more often. However, if you want to see bone mass or water content you'll need to look elsewhere.

Synced with all the other activity data it should give Fitbit users a pretty holistic view of their health metrics. It doesn't have the ability to shows as many of the health metrics as some of the other scales reveiewed here, but with weight

Fitbit dashbaird data

Verdict: The Fitbit Aria is the natural choice for existing Fitbit users as it syncs so well with their Fitbit app and dashboard. But you don’t need to be a Fitbit tracker user to choose the Aria, although you will need to set up a free account there. It looks great, and the LED display is clear and easy to read. We found the Aria to be accurate in its readings, as long as you position it in as close as you can to the same place each time. It doesn't, however, measure as many health metrics as some of the other smart scales reviewed here. If you want more metrics and are a Fitbit user then you'll need to buy a different scale and input your weight into the Fitbit dashboard manually. If you're happy with just weight and BMI then the Aria is a great choice.

For more details read our full Fitbit Aria review.

Specs: 31.2cm x 31.2cm square, by 3.3cm height.

Syncs via: Bluetooth and Wi-Fi

Buy the Fitbit Aria at Amazon

iHealth Core

iHealth Core
  • Rating: ratingsratingsratingsratingsratings

Price: Core – €129.95, US$129.95; Lite – €79.95, $79.95.

iHealth Core measures: weight and body mass index, body fat, lean muscle, bone mass, water weight, daily calories and visceral fat rating (VFR).

iHealth Lite measures: weight and BMI.

Users: 20

Colours: White

“You are more than just a number, you are beautiful!” says the iHealth scale when you open the box. This is a nice message as it reminds you that whatever the data the scales give you, you shouldn’t hate yourself for them. Get more healthy, change those numbers, for sure – but don’t let your life be absolutely ruled by them.

There are two models available: the iHealth Core (HS6) and iHealth Lite (HS4). You can still find the older Body Analysis Scale (HS5) available online, but this has now been officially replaced by the Core, which has much the same features but a better (if heavier) design.

As it can be synced via Wi-Fi the iHealth Core allows the device to be used by a family much easier as it recognises the user without the phone present. It also pairs via Bluetooth if that’s your preferred connection.

The Lite version (€79.95, $79.95) measures just weight and BMI, and connects only via Bluetooth.

Like the other smart scales reviewed here the iHealth scales wirelessly sync with a mobile app (iHealth MyVitals, on iOS and Android) to graphically and statistically display your latest and historical data, helping you track your progress.

iHealth Core app

Setup is pretty easy, and you can start using it straight away after registering with the app.

Once connected to the iHealth MyVitals App an algorithm can calculate an estimate of your optimal calorie intake for Core users; Lite users will need to manually input this data.

The scales keep up to 200 measurements in its internal memory, so you don’t have to sync every time you step on the scale.

Both can support the highest number of individual users (20) of all the scales reviewed and tested here. Each can set their own goals and monitor their stats on their own apps.

The iHealth scales are part of a wide family of iHealth gadgets, including an activity tracker (the iHeath Wave that notably tracks your swimming as well as steps and so on), oximeter, and blood pressure monitors. Read our iHealth Wave review for more on all these iHealth products.

With this medical angle you can share the information from the scale with your doctor or caregiver if you wish.

Verdict: We like the way that the Core and Lite scales interact with the other iHealth products, and the Core offers a bunch of useful metrics with which to monitor your health. Setup is easy and the app's graphs give a decent visual representation of your health-metric trends as you progress.

iHealth Core specs: 35cm x 35cm square, by 2.85cm height. Syncs via: Bluetooth and Wi-Fi

iHealth Lite specs: 35cm x 35cm square, by 2.85cm height. Syncs via: Bluetooth

Buy the iHealth Wireless Core Scale at Amazon.

Buy the iHealth Wireless Lite Scale at Amazon.

Salter Curve Smart Analyser Pro Scale

Salter Curve Smart Analyser Pro Scale
  • Rating: ratingsratingsratingsratingsratings

Price: £89.99

Measures: weight and body mass index, body fat, muscle mass, bone mass, water percentage, and Basal metabolic rate (BMR).

Users: 8

Colours: White

Salter is a well-known scales manufacturer, and has been weighing people for nearly 50 years – unlike the new kids on the block with their fancy digital monitors. But Salter has a range of electronic scales to match the best functions of the other smart scales reviewed here.

The Salter Curve Analyser Pro scales (9192) have an easy-to-read LED display, which shows you your weight and other metrics when you step on. You can also use the display to input your height, age and gender details.

The instructions go further than most of the scales reviewed here, explaining the metrics, and giving healthy averages to aspire to. Remember that we’re all individuals and depending on your body you may not conform exactly to these generalised averages.

The scales look good, and will fit into to most home environments.

We found setup a little confusing at the start, but we were up and running (or rather standing) reasonably quickly once we had paired the device with our phone via Bluetooth. Other online reviews back us up on these Bluetooth teething problems. It took a couple of goes to get the data to sync from the scales to the Mibody app (iOS and Android). It worked fine for a couple of days but if you move the scale you have to go through what appears a simple procedure but actually frustrated the hell out of us. Some days – despite a successful pairing via Bluetooth – we could see the weight on the scale's display but it refused to sync with the app. In our opinion this negates the term "smart" in the smart scales stakes.

You use the app to set yourself goals on the various metrics. You can also input other personal data, such as your waist measurement, which some health professionals believe is a better indication of your health (when considered with your height) than your BMI. You can also input your neck, upper arm, chest, thigh, calf and hips measurements. None of the other scales has this abililty.

Salter Mibody app

While clear, the app's graphs were a little flat compared to other more visually engaging apps seen with the other smart scales reviewed here.

There are Child and Athlete modes to distinguish between types of user.

Like the iHealth scales the The Salter Curve Analyser Pro can sync with other medical devices such as a blood pressure monitor. It comes with a generous 15-year guarantee, and three AAA batteries.

Verdict: Salter is an established brand in non-digital scales. The Curve Analyser Pro looks great and measures just about everything a set of smart scales can. We found initial setup to be hit and miss, and syncing data via Bluetooth sometimes just didn't work – the whole procedure seems needlessly complicated when it should be step on and everything just works. For this reason we can't really recommend the Salter scale, which is a shame as it is otherwise an interesting device.

Specs: 30.6cm x 33.6cm, by 3cm height.

Syncs via: Bluetooth

Buy the Salter Curve Analyser Pro at Amazon.

Koogeek Bluetooth Wi-Fi Smart Health Scale

Koogeek Bluetooth Wi-Fi Smart Health Scale
  • Rating: ratingsratingsratingsratingsratings

Price: £55.99, US$79.99

Measures: weight, BMI (Body Mass Index), body fat mass, lean mass, bone mass, total body water, BMR (Basal Metabolic Rate) and visceral fat.

Users: 16

Colours: White

The Koogeek Smart Health Scale measures a ton of health-related metrics. It's difficult to see any it misses out on, and it's available at great prices online.

The Koogeek Scale boasts a stylish modern look, and has a large blue LED display you can’t miss.

It syncs with the Koogeek mobile app (Android and iOS), which displays your weight and other stats in various ways with attractive graphs and historical weight data so you can quickly see your weight trends.

The Koogeek app takes activity data from Apple’s Health app, so you can use this to simultaneously monitor your steps – no need for an extra activity tracker as this uses your iPhone as the step measurement device.

You can view the Steps measured by Apple Health from within the Koogeek app, but it doesn’t send weight data back to Apple Health.

Koogeek app stats

The Koogeek scale can handle up to 16 individual users – but don’t all try to stand on the scales at the same time!

Here’s a great feature for new parents. You can use the scale to measure your baby’s weight, by first weighing yourself then step on the scales again with baby. Koogeek’s app can then check your child’s weight trend.

Set up wasn’t as easy as we found with some of the other scales tested here. We got it eventually but you have to jump through a few hoops getting there. For example, you can’t use the Bluetooth function of the scales if you have other Bluetooth devices active within range of the scales. So if you have an activity tracker on this will stop the Koogeek scales from finding a Bluetooth connection, which is annoying. Indeed any Bluetooth device within range stops the Koogeek’s Bluetooth working.

As some of the other scales tested here don’t have a Bluetooth connection it’s not a big deal, unless of course you don’t have access to a Wi-Fi network at home.

Instead you link the Koogeek to your Wi-Fi, and it syncs with its mobile app that way. Once set up (it took us a few attempts) it works fine.

Other online reviews suggest that it wasn’t just us having setup problems, and this is one area that Koogeek could certainly improve. Some of the app’s English is not so good, but not incomprehensible.

Verdict: The Scale is well built and stylish in looks, and one of the least expensive tested here. It shows your step count by taking this data from Apple's Health app for iOS users, although it can't transfer data the other way. While we liked the design and measuring accuracy, plus the app's look and feel, we did feel that it needs some attention to make the basic sync and setup less bothersome.

Specs: 31.5cm x 31.5cm square, by 2.9cm height.

Syncs via: Bluetooth and Wi-Fi

Buy the Koogeek Smart Health Scale at Amazon. It is also available to multiple clountries via TomTop.com.