Top five smartwatches for 2021

Whether you’re looking for a stylish smartwatch to keep up with notifications such as calls, texts and emails, or a device that can help you track your activity, we’ve got a top-scoring model for you. We’ve tested the latest smartwatches from brands such as Apple, Garmin and Samsung.

The tables below contain the five best smartwatches overall, followed by our expert picks of the best smartwatches for a variety of needs and activities.

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Best overall smartwatches

The smartwatches we've picked out below are our five top-scoring models overall, assessed across parameters such as how they perform when it comes to notifications and smart features, how accurately they track your fitness, how long it takes to fully charge your device and how much battery life you can expect to get and whether they have clear and reactive screens. 

That's not to say each model here is the absolute best in every way, but these perform well enough in all tests to be our best smartwatches overall. 

Best smartwatches for accurate step counting

Walking is a super-easy form of exercise – and best of all it's free to do. If you haven't tended to exercise much in the past, which is often the case for those of us with sedentary jobs, then aiming for a daily step target is a good, gentle way to build up your fitness. 

Any smartwatch will record your step count, but whether it does it accurately or not is another matter. 

The smartwatches below aren't the best on test overall, but they're the best ones if your main concern is step tracking. They track steps accurately both during walks and runs and during everyday household activities.

We've only included watches here which aren't super-expensive. There are other watches which track steps accurately but aren't the best choice if your main concern is step-tracking, as there just wouldn't be any need for you to pay so much. 

How do we test step-tracking accuracy? 

We test how accurately smartwatches log steps during walks and runs, and during household activities, including packing and unpacking the dishwasher, sweeping the floor, going up and down stairs and sitting reading a magazine. 

Some smartwatches wildly overstate or understate step count, missing steps or being so sensitive that they clock up too many. In particular, many smartwatches miscalculate steps during everyday household activities, mistaking any hand movement for you swinging your arm while taking a step. 

Some smartwatches from well-known brands have been out by around 80% in this part of our test.

For more on accuracy, check out our guide to the most accurate smartwatches and fitness trackers.

Best smartwatches with heart rate monitors

If you're worried about your heart health, you should speak to your GP. If, however, you're generally healthy, and you're more casually interested in monitoring your heart rate with a view to getting more out of your workouts, then look for a smartwatch with an in-built heart rate monitor. 

By keeping an eye on your heart rate, you can check that you're pushing yourself hard enough during exercise and recovering enough afterwards. 

Monitoring your heart rate patterns long term can help you spot things that are causing spikes in your day to day life, and motivate you to take a more active interest in your cardiovascular health.

Some watches go much further, allowing you to take ECGs (electrocardiograms) to check for signs of A-Fib (atrial fibrillation). It's important to note that these aren't medical devices – they're more like toys for the worried well. But you can flag anything unusual with your GP and can help you build a more detailed overall picture of your health. 

How do we test heart-rate tracking accuracy? 

We test smartwatches during low intensity exercise, high intensity running and cycling, and while resting, to see how accurately each one can monitor heart rate.

We compare these results to those taken by chest belts, which are known to be much more accurate. 

Again, we see big differences in how accurately smartwatches measure heart rate. 

Some, for example, track accurately during high-intensity exercise but really struggle during low intensity exercise or at rest. One smartwatch we tested from a popular brand was more than 60% out when measuring heart rate at rest. 

Best GPS smartwatches for running

Not all smartwatches have built-in GPS. Some have to rely on your phone's GPS, meaning you'll need to take your phone out with you when you for a run if you want it to track your route and distance. If you leave your phone behind, your distance will be based on step count. 

If you're a keen runner, we recommend looking for a watch with in-built GPS, as GPS-based distance calculations are often (although not always) more accurate than those based on step count alone. 

Be aware that GPS will drain your battery faster, though. 

How we test smartwatches for distance accuracy

All smartwatches are taken on runs and walks along routes of a known length, to see how accurately they can track your distance travelled. Our routes include woods with dense tree coverage. 

Best waterproof smartwatches for swimming

Some smartwatches shouldn't be used in the water at all. Others can be if you've got the right sort of strap, usually silicone. 

Some waterproof watches don't actually give you much in the way of swim-tracking data, but some go into plenty of detail. Some give you lots of useful information such as:

• number of lengths
• pace
• stroke rate
• stroke detection - whether you're doing front crawl, breast stroke or butterfly, say
• distance
• duration
• calories burned
• SWOLF - a measure of your swimming efficiency

Many can't give you heart-rate data in swim-mode, but a few can be paired with a heart-rate monitor chest strap. 

Here are some of the most detailed smartwatches for swimming. 

Water ratings explained

You'll sometimes see wearables' ability to withstand water described according to different ratings. We explain the different ratings you'll commonly see, and what each one means. 

Ingress Protection (IP) ratings are set by the International Electrotechnical Commission (IEC), and refer to the protection provided by the casing of an electrical device in fresh water. 

The first digit after the IP reflects the level of protection against solids, such as dust or grit. The second represents the protection against moisture. An IP code with an X in place of either number means the device hasn't been tested for that element. 

For example, a smartwatch with a rating of IPX7 has been tested for moisture protection, but has not been tested for dust.  

You can also look for a water pressure rating. These are standards set by the International Organisation for Standardisation (ISO). 

Pressure tests are measured in atmospheres (ATMs) and replicate the level of pressure at certain depths of water.

Three tips for picking the best smartwatch

We run every smartwatch through a barrage of tests, checking how well they deal with notifications, to how accurately  they track your fitness and how long a fully charged battery will last. We spend weeks with each device, to assess it for comfort, too. But, performance aside, how do you pick the perfect smartwatch for you?

1. Operating system – there are three main operating systems for smartwatches: Wear OS, Tizen and watchOS. The type of smartphone you own will dictate the operating system you can go for. Wear OS, formerly called Android Wear, will work with both Android and iOS devices, although the features and functions will differ for iPhone users. Tizen will pair with both Android and iOS smartphones. watchOS is Apple's operating system, and is designed to work exclusively with iOS devices.
2. Decide on your budget – smartwatches cost from around £100 to more than £650 and, while you would have once had to spend a lot to get a smartwatch worth buying, have found some good smartwatches for less than £200. Price is by no means an indicator of performance, as more expensive models often have a swankier design but don't offer more features.
3. Features – deciding which features you need is important. Some devices offer the whole gamut of smart functions, including being able to answer calls and  respond to texts or emails without using your smartphone. Others will be more suited to fitness fanatics, with advanced activity-tracking features such as built-in GPS or a heart-rate monitor. Find out more about which features to look for using our how to buy the best smartwatch guide.

An accurate smartwatch is a great way to track progress in the home, as well as outside. Read our exercise equipment buying guide for more on how to get started with a home gym.

Tables updated April 2021