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.

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 scales that will help you maintain a healthy weight and look at other health metrics.

A standard set of digital 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 that sync with a smartphone app.

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 individual’s best ranges may differ depending on various factors. If in doubt discuss these with your doctor.

Common health metrics for smart scales include:

BMI - this 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, 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.

Body fat percentage - this 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.

Lean mass 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.

Visceral fat – this is fat that exists around your vital organs, and is one of the main risks to long-term health.

Body Water Percentage – the rate of water in body composition. 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.

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.

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).

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 either use Bluetooth to recognise each user's phone, or 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 another's, which will confuse the 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 scales (for example, the Salter Body Analyser Scale) can be adapted for use on carpet, and a few others will work well on carpet without needing adaptation - just make sure to compare the first few results with a hard floor to check they're consistent.

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.

Wi-Fi or Bluetooth

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

Best scales 2018 - smart scales reviews

1. Withings Body Cardio

Withings Body Cardio
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 16 November 2018

The Withings Body Cardio does pretty much everything a smart scale can. 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 for sheer number of stats and handy info like how much weight you've lost or gained since your last weigh in. 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.

However, since Withings has removed PWV support from the Cardio, you might be just as happy with the cheaper Body+, which now has an almost identical feature set from as little as £69/$99.

Read our Withings Body Cardio review.

2. QardioBase 2

QardioBase 2
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 16 November 2018

The QardioBase 2 is as smart as it is stylish, offering a good range of body composition measurements, along with handy unique features like haptic feedback or the emoji display. Our only minor gripe is that the app doesn't make the most of all the data it gathers, but it does do more than enough for most.

The price is the only sticking point. The QardioBase 2 sits at a premium price point, and while it offers enough features to justify that price, it's worth remembering that you can get almost as much for a whole lot less from other manufacturers.

Read our QardioBase 2 review.

3. Fitbit Aria 2

Fitbit Aria 2
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 21 November 2018

The Fitbit Aria 2 scales works seamlessly with Fitbit’s dashboard and mobile apps, plus all its activity trackers, such as the Aria, Charge 2 and Ionic. You could use it without the trackers but together they make a great fitness or weight-loss team.

Aria 2 shows less stats than the more expensive Nokia Body Cardio, but everything you need to know at weigh in. It measures weight, Body Fat Percentage and Body Mass Index, and syncs this data wirelessly and automatically to your Fitbit account. If weight loss is one of your fitness goals the Aria 2 is a great tool to combine with your Fitbit activity tracker. 

Read our Fitbit Aria 2 review.

4. iHealth Core

iHealth Core
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 9 April 2018

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.

Read our iHealth Core review.

5. Koogeek S1 Smart Scale

Koogeek S1 Smart Scale
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 18 July 2018

The Koogeek S1 is a budget-friendly alternative to top tier smart scales, but in this case you really do get what you pay for, from tricky setup to Wi-Fi features that we could never quite get to work - and it doesn't help that it can't give accurate readings on even a thin carpet.

It's not all bad though. This is a low price for a scale that measures everything from weight to bone mass, and once you've got it up and running you can sync all the data to Apple Health or Google Fit. There's also support for up to 16 users and a dedicated mode for tracking the weight of babies or pets.

This can't match top-end models for features or reliability. But if you can't afford to drop £100/$100+ on a bathroom scale (and we can't blame you) then the Koogeek S1 will get the job done, with a couple of quirks.

Read our Koogeek S1 Smart Scale review.

6. Salter Curve Smart Analyser Bathroom Scale

Salter Curve Smart Analyser Bathroom Scale
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 9 April 2018

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.

Read our Salter Curve Smart Analyser Bathroom Scale review.