If you’re after the best fitness tracker, you might be feeling overwhelmed by the sheer number of models available. From sleep tracking to stress management, each offers a range of features at a different price point. The good news is we’ve spent countless hours testing some of the latest fitbits, Garmins, Apple watches and budget health bands to find the best of the bunch. Below, you can see the results of our in-depth testing process.
For most people, the best fitness tracker will offer a decent range of features and a reasonable degree of accuracy — all for a good price. And with January quickly approaching, now is a great time to start looking, as many of our favorite gadgets look set for some huge discounts across the sales event.
The new Apple Watch Series 8 (opens in new tab) manages to tick all of our boxes; it’s not drastically more expensive than the previous Series 7 (opens in new tab) model, packs in plenty of health-tracking features and it’s incredibly accurate to boot. That’s why it currently tops our list.
Fitbit Charge 5 |
Was $149.95 Now $99.95 (opens in new tab)
One of our favourite models, the Fitbit Charge 5, is currently 33% off at Amazon — saving you $50. It features a built-in GPS tracker, stress management tools, and sleep tracking. Choose from black, white and steel blue.
However, the Apple Watch feels very much like a ‘smartwatch for fitness’ rather than a straightforward fitness tracker — plus it only really works with iPhones. If you’re after a simpler option without all the bells and whistles, you might prefer the Xiaomi Smart Band 7, which happens to be our favourite budget option. Or maybe you want a fitness tracker with a sophisticated look, in which case we loved the Withings ScanWatch (opens in new tab) (compatible with iOS and Android).
In brief, the Apple Watch won't suit everyone, which is why we’ve highlighted the standout feature of each watch in this guide so you can see which model is best for you. For even more options, check out our guides to the best Fitbit (opens in new tab) and best Garmin watches (opens in new tab).
Best fitness trackers
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If you're looking for great GPS and heart rate hardware, The Apple Watch Series 8 is a fantastic health and fitness watch.
Apple really does offer best-in-class when it comes to health and safety features. In the Series 8, you’ll find an ECG monitor that can detect abnormal heart rhythms, a blood oxygen monitor and sleep tracking too. There’s also an advanced gyroscope for fall detection, as well as ovulation tracking for those with a menstrual cycle. These are all features that you can find in other trackers, but in our experience the heart-tracking capabilities of Apple outstrip its competitors.
On top of that, the watch has an app library that’s bigger than all of its rivals put together. You can find second-party apps that will improve your yoga flows, help track your workouts and guide you on meditations. Compared with its predecessor, the Apple Watch Series 8 also offers more in-depth data on activities like running, including heart rate zones. You can even create custom workouts and save them to your watch.
But it’s not without its faults; the watch is only compatible with iPhones and battery life only lasts for one day. Still, we think the model is the best combination of value, features and performance available on the market.
- Read our full Apple Watch Series 8 review (opens in new tab)
A Garmin Fenix 7 is the best fitness tracker to get if you want the most comprehensive set of built-in exercise features available. These stand out when you bring other hardware into the mix.
The Fenix 7 series can connect to heart rate straps and foot pods, bike turbo trainers, and even Garmin’s bike lights. You can download continents’ worth of maps to the watch’s internal memory and plan hike, bike and run routes so you can leave your phone at home.
It lets you download music and podcasts from some of the most popular music services, including Spotify and Deezer. And the MiP screen only becomes clearer in bright sunlight, so tracked outdoor sessions won’t kill the long-lasting battery.
Its heart rate and GPS accuracy are great, and the presentation of stats like training load and VO2 Max seems tailored for the fitness enthusiast.
A Garmin Fenix 7 may be a bit much if you just want to track 5km runs a couple of times a week. It’s not light and it’s not cheap. The bulk isn’t ideal for sleep tracking, so consider Garmin’s Versa 2 if you like the sound of Garmin’s style but would prefer something smaller.
That said, Garmin’s watches are less intimidating than they once were. The Fenix 7 has a touchscreen and a quick swipe up from the watch face gives you a neat run-down of all your important daily stats. It has encyclopaedic features, but works well for casual all-day tracking too.
- Read our Garmin Fenix 7 Sapphire Solar review (opens in new tab)
The Xiaomi Smart Band 7 has joined the flock of one of the most popular wearable brands in the world, offering users features often reserved for premium-priced wearables.
For $54.99, this fitness tracker is hard to beat for the number of features. Closely resembling the Fitbit in looks, the crisp 1.62'' AMOLED high-resolution display is glare resistant and 25% larger and brighter than its predecessor – the Xiaomi Smart Band 6.
The Smart Band 7 is iOS and Android compatible, pairing with its own Mi app to give access to data like heart rate, oxygen monitoring, sleep, and workout analysis. You can also follow guided meditations via the app and check in on your daily stress level data. Xiaomi has thrown the kitchen sink at fitness enthusiasts, offering GPS tracking and 110 sport and fitness modes, including swimming (the watch is 50 meters waterproof) and yoga.
We loved the female health management feature that allows you to track your periods and form patterns between your workout data and health stats. However, we found that a few features lacked accuracy, including sleep (and sleep stages) data and workout stats like calories and distance. The touchscreen also became unresponsive during sweaty workouts, which could be frustrating for activities like running or CrossFit.
- Read our full Xiaomi Mi Smart Band 7 review (opens in new tab)
Garmin has cut a few corners with this watch to drive down the price, but you can’t really tell. The main thing the company has done is switch out its metal casing for a plastic one, but unless you’re continually bashing your watch against a hard surface this will make little difference.
As a result of the above, this watch packs in all the features a runner could need at a lower price point. It has downloadable maps, so you can venture off-road without losing your way, and excellent multi-band GPS for accurate distance recording. The maps app even allows you to punch in a particular interest point and the watch will find a running route for you.
This is coupled with VO2 Max (opens in new tab) tracking, blood oxygen monitoring and the ability to analyze performance via the popular ‘Training Status’ feature. Its accuracy was also excellent when we tested it, only showing a few small lags when recording heart rate increases. All this comes in at less than $500, which is genuinely a bargain for a Garmin watch.
Our only small complaint about the watch is that the maps app proved a little fiddly to use — more so than on other models like the Fenix 7. However, as this is a software issue, we think the problems we came across are likely to be ironed out in future updates.
- Read our full Garmin Forerunner 955 review (opens in new tab)
The Fitbit Sense is our favorite model from Fitbit, thanks to its combination of features and sleek AMOLED display. It’s relatively well-priced, too, regularly discounted to $229.95/ £219. While you won’t get all the high-end features found on Garmin watches – there’s no downloadable maps and the GPS functionality isn’t as impressive – you do have some other tasty extras, such as the EDA scanner. This measures ‘stress’ by basically reading how sweaty your hands are – if the model senses that you’re feeling hassled, it will suggest some meditation practices.
The watch also comes with an ECG scanner, which offers some insight into your heart health and will give you alerts if your heart rate is unusually high or low. When we tested it out, we found that the heart rate monitor was fairly accurate when compared to the Apple Watch Series 7 model.
Like a lot of other modern wearables, the Sense has a ‘Daily Readiness’ score that guides you on how much you should push yourself at the gym. Been working out too much and not sleeping enough? It’s likely the tracker will tell you to skip exercise and rest for the day. This score adapts as the tracker gets accustomed to your patterns.
We liked the overall design of the watch too; it’s not so clunky that it feels uncomfortable to wear during sleep. The large screen makes the display easy to read, even in sunlight, and we were impressed by the six-day battery life. Our only real issue with the tracker is that it doesn’t allow you to download and listen to music, unless you’re specifically using the Deezer or Pandora app.
- Read our full Fitbit Sense review (opens in new tab)
We reckon that the Charge 5 is the best Fitbit for most people. If you have your heart set on a Fitbit, you just have to decide whether you’d prefer this or the bigger, more expensive Fitbit Sense.
This model is much smaller. It’s a band, not a watch. And you don’t get the downloadable apps available on Fitbit’s Versa and Sense — like Spotify, for example. If you want to go for a run and listen to music, you’ll have to use your phone if you’re using a Charge 5.
However, the sheer amount of stuff Fitbit packs into the Charge 5 is impressive. It has full GPS, for phone-free route tracking. It has the EDA stress sensor Fitbit introduced in the Sense watch, and even an ECG sensor. This analyses your heart rhythm to check for abnormalities, using hardware completely separate from the optical heart rate reader on the back.
It’s rare to see a fitness tracker this small that is so comprehensive in the stats it can gather, and Fitbit’s sleep tracking is among the best around. However, to see the Fitbit Charge 5 at its full strength you’ll need to sign up for Fitbit Premium. It costs $9.99/£7.99 a month and the watch includes a 6-month trial. While a Charge 5 works fine without it, fitness plans and even blood oxygenation readings sit behind this paywall.
- Read our Fitbit Charge 5 review (opens in new tab)
The Whoop 4.0 bucks nearly every trend going. The wearable dismisses a shiny touchscreen in favour of a discrete “sensor suite”, the usual watch-like buckle is substituted for a woven, elasticated strap, and the step counter which won the likes of FitBit so many fans has been omitted entirely.
Instead, what you get is continuous monitoring of an array of health metrics including heart rate, skin temperature and heart rate variability, as well as in-depth sleep tracking. This data is used to produce three digestible daily scores; strain, sleep and recovery.
Having trialled the Whoop 4.0 for a month, we found this alternative approach had both benefits and drawbacks. The lack of a screen or in-built GPS isn’t well-suited to endurance activities as we were unable to track or check their pace during running sessions. However, the discreet, screenless design felt durable and showed no signs of damage after being smacked with a kettlebell or submerged during a wild swimming session.
The simplified strain, sleep and recovery scores allowed us to train smarter at a glance (taking rest days when needed to boost our recovery) while the well-presented app provided plenty of in-depth data for stat fiends to sink their teeth into.
Also, when following the recommendations of the sleep coach on when to go to bed and how much sleep we needed, we were able to improve our recovery score and felt noticeably fresher the following day.
- Read our full Whoop 4.0 review (opens in new tab)
The Amazfit GTR 3 is a fitness tracker that looks a lot like a smartwatch. It has a super-sharp 1.39-inch OLED screen similar to the display of the Samsung Galaxy Watch 4, which is a lot more expensive.
Its outer casing is aluminium, and it has a rotary crown controller similar to the Apple Watch Series 7’s. The back of the watch face, which sits on your wrist, is plastic. But this just sums up what the Amazfit GTR 3 is all about. Amazfit tries to pack in features and higher-end style where you’ll notice it, and leaves out more expensive parts where you won’t.
It has full GPS, provides blood oxygenation readings and has an optical heart rate reader with six light-sensing photodiodes. Amazfit packs in a dizzying 150-plus workout modes, menstrual tracking, Amazon Alexa support, 5ATM water resistance and fantastic battery life of up to 21 days (6 days if you use the always-on screen mode).
The message is clear: the Amazfit GTR 3 does a lot, for not all that much money. It’s important not to expect stellar depth or accuracy, though. The heart rate sensor is not as good at tracking interval workouts as an Apple Watch or Garmin Instinct 2, and unlike the “Pro” version of the GTR 3, you can’t load this watch up with music for phone-free workouts.
- Read our Amazfit GTR 3 review (opens in new tab)
We've tested both the Withings Scanwatch and the recently released Withings ScanWatch Horizon — and the original model remains our favorite. It expertly blends a fashionable wristwatch design with high-tech health and fitness tracker.
We loved testing this sophisticated watch, playing with features like on-the-spot oxygen and ECG monitoring, sleep and fitness tracking, and basic metrics on calories and step count. It’s brilliant for gathering comprehensive data on your health, helping to provide a holistic picture of your wellbeing.
The crown on the side of the watch flicks through features on a small digital screen within the clock face, bringing old and new together into one medical-grade wearable.
The Withings ScanWatch is iOS and Android compatible and partners with the Health Mate app, where you have access to a dashboard of data like blood pressure, average heart rate, and more in-depth sleep analysis. You can also link up to third-party apps including Strava and Apple Health, and set up weight loss goals, macro tracking, or step count. It’s even waterproof (up to 50 meters) if you fancy taking it for a swim, but it’ll set you back a cool $279.95/£249.95.
- Read our full Withings ScanWatch review (opens in new tab)
We were impressed with the performance of the Oura ring during our month-long testing period. Its accurate sleep tracking is the real stand out feature; we found that whenever we woke up feeling groggy and poorly rested, the Oura ring was able to show us exactly when our rest had been disturbed and how it had affected our REM sleep.
The ring is able to take this data and make suggestions too. For example, our tester was advised to shift their workouts to earlier in the day and found that doing so had a positive impact on their sleep latency (how long it took them to fall asleep.)
As the ring is so small, it doesn’t have a screen. Instead, you’ll have to rely on a companion app to look at most of your health data. We didn’t find this to be a massive issue, although it does mean there’s no easy and quick way to check things like your heart rate when you’re in the middle of a workout.
There’s an impressive amount of data gathered by the ring. It measures your heart rate at various intervals throughout the day, along with your heart rate variability at night, to help check for potential health problems. And it has a helpful ‘readiness’ feature that will let you know if you should prioritise exercise or rest.
We did find that it’s not 100% accurate at tracking all health metrics. For example, we found it massively over estimated calorie burn during our testing period. And its ‘auto-detect’ feature often attributed the wrong exercise to our workout, for example recording a HIIT session as a weights session.
Despite this, we really rate it, thanks to its unusual design and brilliant, unmatched sleep-tracking ability.
- Read our full Oura ring Generation 3 review (opens in new tab)
If you want a Fitbit that’s similar to the Apple Watch, the Versa 3 has a ton of the same features… It can track your heart rate, temperature, blood oxygen level (spO2), as well as the usual steps and calories, but it’s half the price of an Apple Watch Series 7. In fact you could put the money you save toward a Fitbit Premium membership ($9.99/£7.99pm), which opens up access to loads of extra content and features.
One thing Fitbit is really good at is sleep tracking, and the Versa is no exception. You can monitor your sleep patterns through the night and the spO2 sensor will measure your blood oxygen levels so you can track the data when you wake up (although bear in mind some of the stats can only be accessed if you have a Premium subscription).
Battery life is hard to rival, with a claimed six-plus days of use from a single charge, and 12 hours when using non-stop GPS. You can also use the metallic charging point to give it a day’s worth of battery charge in just 12 minutes.
As you’d expect, the fitness tracker syncs with your smartphone (iOs, Android) and it has an inbuilt speaker and mic so you can take calls on the go from your wrist and use the voice-controlled Amazon Alexa or Google Assistant.
Love swimming? The Versa 3 is waterproof up to 50m, and you can also use it to track pool lengths. Another big pull is the intensity map feature – it’ll use your heart rate data to reveal the intensity at which you exercised over different stages of the workout.
Our main gripe is you can’t download playlists and listen to music offline, unless you have Deezer or Pandora.
- Read our full Fitbit Versa 3 review (opens in new tab)
If you’re on a budget, then the Huawei Band 3 Pro delivers a big bang for its buck – with inbuilt GPS, touchscreen display, heart rate monitor and dedicated swimming mode.
The color screen is easy to read even in direct sunlight, so it’s good for runners and fans of outdoor exercise. The GPS could be a bit quicker to connect, but it’s accurate even in built-up areas and a lot of trackers in this price range don’t even have this feature. It also provides real-time feedback on workouts, including VO2 Max and recovery times.
If you’re a fan of sleep tracking, this fitness tracker offers more than 200 potential solutions to better rest, and its ‘TruSleep’ feature uses the heart rate monitor for more accurate results. It can even separate your night into light sleep, REM (important for memory, emotional processing and healthy brain development) and Stage 3 deep sleep, and rate your breathing quality.
The Huawei Band 3 Pro has a phone finder feature, and you can see incoming calls with caller ID, receive message alerts and certain notifications from apps, but to be honest we found the way you view these notifications slightly awkward.
There are no physical buttons on this fitness tracker, which means when you’re sweaty, exercising in the rain or in the pool, touchscreen controls can become a bit of an issue. There’s a single touchscreen button under the main screen but one that sticks out on the side would be more useful.
For those of you who wear your watch in bed and are prone to moving about, you will probably find the fact that the screen doesn’t automatically turn off rather annoying. There is an option to reduce the brightness at night in the settings, but bizarrely this is not enabled by default.
Editor's note: This item is currently in the process of being reviewed. Once it has been tested, this guide will be updated accordingly.
How we test fitness trackers
You can trust our recommendations when it comes to picking the best fitness trackers; each product on this list has been tried and tested by our expert fitness team. We gathered a range of top wearables and put them through their paces, wearing them for a variety of activities including running, swimming, gym sessions, HIIT workouts, and more.
We looked at the features, feedback and metrics on offer from each one, from the industry-standard step-counters to more detailed data like heart rate variability and blood oxygen saturation. Other factors considered included their design, comfort and performance, with our experiences in each area used to decide a final score out of five stars.
Garmin vs Fitbit
Garmins are for fitness nerds, Fitbits are for those who would prefer a tracker with a more friendly face. That has been the traditional take on these two brands, and it still mostly holds up in 2022.
Garmin’s best fitness trackers offer significantly better core stat accuracy and reliability than Fitbit in our experience. A recent Venu/Fenix/Forerunner wearable will typically deliver superior heart rate readings to a Versa/Charge/Sense watch.
The latest Garmins also have more advanced GPS, with support for multi-band reception and Galileo. Don’t know what those are? It means you’ll get reliable signals across a wider range of locations and environment types — but that probably won’t have much of an effect if you plan on going for runs around your local park.
Garmins are clearly the obvious pick for the hardcore crowd. However, Fitbits tend to have a more deliberate sense of style, and their prices don’t reach anything like the heights of the top Garmin trackers.
The “high end” Fitbit Sense and Charge 5 cost about as much as some entry-level Garmin models. These two in particular also have a couple of features not seen in Garmin rivals.
They have ECG/EKG hardware, to monitor sinus rhythm, and an EDA sensor (which uses the ECG hardware) that estimates stress levels. Both of these require active participation — you hold a finger to the watch bezel — but are nifty health-related extras.
Apple’s Heart Study from 2019 found 34% of those who were given an alert from their Apple Watch’s ECG did indeed have atrial fibrillation. It can be a genuinely useful feature from a health perspective.
Fitbit vs Apple Watch
Fitbit makes a wider array of wearables than Apple. There’s the affordable, petite Inspire 2 and its upmarket sibling the Fitbit Luxe. The trim Charge 5 has all the features a fitness tracker needs to less outlay than an Apple Watch.
Conversely, all Apple Watches look roundly similar aside from how much of the front is covered by screen. There’s the lavish one, the more affordable one, and the old one: Watch Series 7, Watch SE and Watch Series 3.
Like that look? The Fitbit Versa and Sense watches get much closer to the Apple Watch style. However, even these last significantly longer than Apple’s watches off a charge. Stamina varies between models, but at least 4-6 days is the norm for Fitbit, compared to roughly a day or so with an Apple Watch.
This makes Fitbits better for sleep tracking, and Fitbit probably still has the best sleep tracking software on the market right now (apart from maybe the Oura ring). However, to get the most out of a Fitbit you’ll need a Premium subscription ($9.99/month). This offers additional stats and proper longer-term health metrics, as well as loads of workouts and mindfulness sessions.
An Apple Watch, regardless of the model you get, will have a better heart rate sensor than a Fitbit’s. Even the best Fitbit Versa 3 and Sense trackers aren’t close to Apple’s for reliability and accuracy.
The Apple Watch also has the best app ecosystem of any watch. Want apps for third-part platforms, yoga tutorials or mindfulness exercises? Apple can’t be beaten in this area.
Apple Fitness+, the equivalent to Fitbit Premium, is also more high-end than its Fitbit rival, packed with loads of high-quality video classes.
If the Apple Watch had Fitbit’s battery life, this would be a fairly clean sweep for Apple. But it doesn’t, and many will find a Fitbit easier to get along with longer-term.
What is a fitness tracker good for
Back in the early days a fitness tracker was a step counter. Iconic models like the Fitbit Zip and Ultra would attach to your shorts or jeans, not your wrist.
Today, trackers can do a lot more, but they still count your steps. Most will measure your heart rate 24/7: handy for exercise, and your resting heart rate is a decent fitness and health indicator, as explored in a BMC Cardiovascular Disorders (opens in new tab) study published in 2020.
You can use a fitness tracker to monitor your sleep. And they are better-suited to the job than a smartwatch as trackers often last a week or more between battery charges.
Some fitness trackers have a feature that lets you sound an alarm on your phone should you misplace it. And nowadays plenty have advanced health and fitness features.
Any fitness tracker with GPS is a good tool for runners. Many can measure your SpO2 blood oxygen saturation, and a few high-end models have an ECG sensor. There are many stories of this alerting people to atrial fibrillation, a potentially life-saving move.
Fitness trackers frequently have “stress” monitoring, and guided mindfulness breathing exercises to help you lower that stress level. Even cheap fitness trackers will also relay notifications received, and this can be a useful if you want to spend less time on your phone after work.
Put the phone in another room, and you can still quickly check for important calls or emails with a quick wrist flick — no chance of getting sucked into YouTube/Facebook/Instagram for an hour.
Are fitness trackers accurate
Fitness trackers record a bunch of metrics, each of which introduces accuracy headaches. For step counting, how does a tracker separate steps from hand movements while you work sat at a desk? How can a yoga tracking mode really judge calories burnt when it does not know your muscle tension or perhaps even the positions you adopt?
The best fitness trackers now offer good reliability in a few crucial areas, though, heart rate and location — which look at the distances you run or walk.
We find Apple Watches and some of the latest Garmin watches, like the Fenix 7, are top-tier performers for heart rate tracking. Apple led the pack for years, but others are starting to catch up. A 2019 study published in the Journal of Medical Internet Research (opens in new tab) found the Apple Watch offered “clinically acceptable accuracy” for HR tracking during exercise, a higher standard than it might sound — and that was for an old Apple Watch variant. However, it also found the watch overestimated calories burnt.
Almost all fitness trackers with GPS will provide fairly good distance stats, particularly if you give them time to lock-on properly before starting your session.
A lot of other trackers still struggle a little with heart rate readings, though. Interval training and very high exertion in general can be problematic, although in truth this is not a huge issue for most people. Are you really going to pore over the heart rate graph in your tracker’s app?
SpO2 (blood oxygenation) readings can be more problematic, because we find most wearables can throw out highly suspect results at times. You will often get better results on a second or third attempt, but we frequently see readings that suggest we should head straight to the hospital from high-end trackers.
That said, a study published in Nature (opens in new tab) concluded the old Apple Watch Series 6 is a reliable enough way to monitor SpO2 in patients with lung conditions.
The best way to approach a fitness tracker’s stats is to compare your exercise results to your own, from previous sessions. Comparing with a friend’s tracker will expose the way different brands’ algorithms color the results.
You should also make sure your tracker’s strap is snug and firmly strapped on before starting a tracked exercise session. This will get you the best results from the heart rate sensor.
Can fitness trackers measure blood pressure
Right now there’s only one mainstream consumer wearable that has true standalone blood pressure monitoring, the Huawei Watch D. And it is not widely available.
Samsung has offered blood pressure readings in its top watches since 2020’s Galaxy Watch 3. However, the feature is only unlocked in certain countries/markets, and is much more limited than the Huawei Watch D’s version.
Where the Huawei Watch D adopts the method used by blood pressure cuffs with a specialist strap that inflates, the Galaxy Watch uses the heart rate reader on the back to evaluate pulse transit time. Fitbit (opens in new tab) is researching a similar method, using pulse arrival time.
However, such methods that do not demand bespoke hardware do need to be regularly recalibrated using a traditional blood pressure cuff. Samsung says results should be taken with one every four weeks, for example.
Rumors of a blood pressure feature for Apple Watches have circulated for a while, but the latest report suggests we won’t see it released until 2024. However, you can use an Apple Watch to log blood pressure readings taken elsewhere, in the Apple Health app. Apple sells Withings’s BPM Connect smart blood pressure cuff at the Apple Store.
Blood pressure via a wearable? It’s not quite there yet. And as the Huawei Watch D is expensive, hard to get hold of, and something we have not tested, you are better off with a more traditional cuff-style design for now.
Why is GPS important in fitness trackers
GPS is arguably the most powerful tool for fitness trackers. It’s why runners, keen walkers and cyclists should make sure their next fitness tracker has it.
GPS triangulates your position with the help of satellites. One of these satellite arrays is called “GPS”, but today’s best watches also support others like GLONASS and Galileo. Each of these satellite arrays is maintained by a different country, or set of countries.
By tracking your location, fitness trackers can produce maps of your runs, hikes and rides. These make historical records much more useful, so you can actually remember which workout an entry refers to.
Accurate distance data is also important because it affects so many other readings. If the recorded distance is too low, the tracker will think you are slower than you are. And this in turn could affect fitness metrics like VO2 Max. It works the other way around too, of course — too long a recorded distance and the tracker will say you are faster than you really are.
We always recommend a full GPS watch to runners in particular, but there is a second type of GPS. It’s Connected GPS. This is where the tracker does not have its own GPS chip, but can take GPS data from your phone, over Bluetooth.
Many cheaper trackers without GPS have Connected GPS. And if you plan on running with your phone anyway, to listen to music or podcasts, it’s a decent stand-in.
With no GPS at all, your tracker has to extrapolate distance using its motion sensors. It can count your strides and evaluate the pace of them to differentiate between running and walking. This can work pretty well with a good algorithm running behind the scenes, but GPS is better. And considering how cheap Connected GPS wearables get, we don’t recommend entirely non-GPS watches to many folks these days.