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The right fitness tracker or activity tracker can provide you with an accurate, comprehensive and easy-to-understand view of your health, whether you’re running, cycling, swimming, monitoring your heart rate or trying to up your step count.
But paying for features that you won't use, or that aren't designed for your type of exercise, is a common mistake. Plus, the worst trackers we've seen won't track your activity accurately and show you irrelevant data. Our guide can help you settle on the right model, so you can track your fitness and activity with a device you can trust.
Go straight to our fitness tracker reviews to compare all the models we've tested.
Here’s a selection of the top-scoring fitness trackers from our lab tests.
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Full Access first month £5, then £11.99 per month, cancel at any time
Full Access first month £5, then £11.99 per month, cancel at any time
Full Access first month £5, then £11.99 per month, cancel at any time
Full Access first month £5, then £11.99 per month, cancel at any time
Full Access first month £5, then £11.99 per month, cancel at any time
We don't take accept any free samples. We buy every product we test to make sure we're getting the same quality you would.
We know you want to get as much use out of your fitness tracker as possible so our tests are extensive. Fitness trackers claim to track a lot of metrics, the most common being heart rate, steps and distance. We'll test how well it does these, and if it claims to track your blood oxygen levels, we'll test the accuracy of this technology too.
Glossy marketing pictures won't tell you if a fitness tracker is comfortable to wear when exercising, resting or sleeping, but our tests will. Our experts will evaluate the quality of the tracker's screen and how useful the stats and graphs are that it shows you about your health. We'll also tell you how good the paired smartphone app is. Most fitness trackers connect to both Android and iOS (Apple) smartphones, so we check to see if there are any differences in your experience on the paired app depending on your phone.
Fitness trackers collect your personal health data, which must be kept secure to avoid it being used against you. Our privacy and security testing will check to see if there are any serious vulnerabilities that could be exploited. Read more about how we test fitness trackers.
You can pick up a wide variety of models from tech retailers and online marketplaces. We've highlighted a few of the most searched-for retailers that have a range of fitness trackers to help you narrow it down:
You can buy a tracker for as little as £2 or you could pay close to £250.
Be wary about going too cheap – you could end up with a device that's fiddly and frustrating to use. You also run the risk of your data not being protected. We tested ultra-cheap fitness trackers and smartwatches (dead ringers for Apple, Fitbit and Samsung) and each one had concerning security flaws. Read more about our investigation into security issues in cheap smartwatches and fitness trackers.
Generally speaking, you'll need to pay at least £50 for a good one, though we have tested some one that's frequently available around the £35 mark that we're happy to call Great Value. Great Value fitness trackers combine good performance with a cheaper than average price. Discover our Best Buy fitness trackers and Great Value fitness trackers.
Security and software support is important to consider when buying a fitness tracker, dictating how long the brand continues updating the device with new features and security patches, to guard against emerging threats.
We estimate the 'lifetime' of a fitness tracker – the average time we’d expect one to last before it breaks down or deteriorates significantly – is 4.3 years. This is based on robust analysis of recent product surveys and is a conservative estimate, so we’re confident that the genuine average is above this value.
We reached out to the biggest brands to find out more about support policies for wearables (smartwatches and fitness trackers). As you can see, many are falling well short of this measure.
Other fitness tracker brands that did not provide us with information on minimum update support periods include Amazfit, Huawei and Realme.
While you might not be at immediate risk if you're using an unsupported device, it's obviously much better to choose one that you know will receive update support for a decent period of time. For more information, read our guide to smart devices and security.
Some fitness or activity trackers pack in a wide range of sensors to track everything, from steps and heart rate to your exact location and even the intensity of sunlight, to let you know when it’s time to reach for the sunscreen. This can result in more detailed feedback but, as revealed by our tough tests, not every device is accurate.
On top of that, having too many sensors can reduce the battery life, or make the device more complicated to use (we rate ease of use in our tests too), so it's important to get the right balance.
A pedometer is the most basic sensor and one you’ll find in any activity tracker. This will count your steps and can often capture distance, too, based on an estimation of your stride length. We put the step counter through its paces in our tough lab test and check the accuracy.
If your wearable has built-in GPS, it can track distance more accurately – as long as the GPS works well and doesn’t drop the connection. Many fitness trackers can be paired to your mobile phone to make use of its GPS; however, built-in GPS is useful if you want to jog or cycle without having to carry your phone.
Most now come with a heart rate monitor which will report on your average heart rate, and periods of peaks and troughs – useful for tracking improvements in your fitness.
Again, accuracy is important, and this can vary a fair bit between different makes and models. We rate this as part of our lab tests, too, to find good trackers that don't miss a beat.
More accurate heart-rate monitoring should also mean more accurate VO2 max estimates (estimates of your maximum rate of oxygen consumption) if your tracker has that function. VO2 max data can be useful for climbers, people preparing for a particular event and athletes.
Most trackers, including cheap ones, will now keep an eye on your sleep, including motion sensing to see whether your sleep is disturbed, and offering you an estimate of how much of your sleep has been spent in REM, or light or deep sleep. Some have a sleep cycle alarm, meaning your tracker will wake you up at the optimal time in your sleep cycle that’s close to your desired wake-up time. If you're interested in this, we have a dedicated guide on how to track sleep with a smartwatch or fitness tracker.
Most fitness trackers should be at least splashproof (ideally IP67 or IP68-certified for immersion in water). Note that this doesn't meant the watch is suitable for swimming; this capability is usually measured in atmospheres (ATM). For example, 5 ATM means a tracker should be water-resistant up to a depth of 50 metres.
There's a range of ratings which show how splashproof a watch is or if you can swim with it.
Some fitness trackers shouldn't be used in the water at all. Others can be if you've got the right sort of strap, usually silicone. You should also avoid using a watch in hot showers or saunas, and bear in mind that the level of water resistance is not permanent and may reduce over time.
Some models don't give you much in the way of swim-tracking data, while others will tell you the number of lengths, your pace, stroke rate and swimming efficiency. A few can be paired with a heart-rate monitor chest strap.
If you already use an app on your smartphone or wearable, such as Strava or running app MapMyRun, you won’t want to lose access to your data or the in-depth analysis a dedicated app can offer. Smartwatches are more likely to offer compatibility here, allowing you to pair with app services and sync the data from your wearable.
If you want to listen to music on your run without taking multiple devices out with you, look for a smartwatch (rather than a fitness tracker, generally speaking) that has built-in storage for your tunes. You'll need a Bluetooth headset as well, though. Music management is not a feature that's commonly found on activity trackers, so head over to our smartwatch reviews to browse all the models we've tested.
Fitness trackers are a great way of recording progress in a home gym, as well as outside. Read our exercise equipment buying guide for more on setting one up.
You might take for granted that your shiny new fitness tracker or smartwatch does the job it claims to, but this isn't always the case.
We've found fitness trackers and smartwatches that over or understate data, or that are unreliable and inconsistent day to day, making hard for you to get an accurate picture of your progress.
One of the worst products we've tested miscalculated step count by 66%, meaning you'd only have taken 3,400 steps when it tells you you've taken 10,000.
If you're using a smartwatch or fitness tracker to help you achieve a specific goal - say, reaching a daily step count target or running a certain distance - you'll want to ensure it's accurate. We put our wearables through a range of scenarios, including an outdoor run, to see just how accurate each one really is.
We check how accurate they are at measuring steps, distance and heart rate. And we take consistency into account as well. If a tracker is accurate on some days but not on others, you won’t know whether you’re improving.
For more details, check in with our guide on how we test fitness trackers.
Using your wearable could become irritating if you find yourself needing to charge it frequently. Generally, activity trackers have the advantage over smartwatches here – they're simpler devices with smaller screens, so won't drain as fast.
Most activity trackers have a battery life that ranges from a couple of days to a couple of weeks. Some models use coin-cell batteries, like a watch, which last several months before needing replacing.
Smartwatches, on the other hand, may need charging every day after heavy use.
All the wearables we test are measured for battery life in our labs. Browse all our fitness tracker reviews to find the perfect combination of features and battery life.
Our tests go the extra mile, using specialist lab equipment to check the accuracy of the tracking capabilities of each device. Our panel of users gets to grips with the trackers over a number of weeks, so that we can also tell you how easy to use and comfortable to wear each device is.
Read more about how we test fitness trackers.