Want more help deciding which is best for you? Read our buying advice for the Best Fitbit 2019

1. Fitbit Charge 3

Fitbit Charge 3
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  • Reviewed on: 1 November 2018

The best all-round Fitbit

Fitbit has successfully redesigned its most popular product with the Charge 3. For first-time buyers, you won’t find a better-featured activity tracker on the market at such a fair price. It tracks Steps, Distance, Calories burned, Active Minutes, Floors Climbed, Heart Rate, and Sleep Stages, and can connect to your phone's GPS if you want to map your runs.

You also get a full set of on-screen notifications such as Caller ID, texts, Calendar, WhatsApp, and others. It even has its own Weather app.

Given that it comes two years after the Charge 2 we think it’s a warranted upgrade, particularly if you desire the longer battery life (7 days) and full waterproofing.

The Charge 3 should prove very popular come Christmas and especially for those New Year resolutions. It is a worthy upgrade to Fitbit's most popular-ever fitness tracker.

Read our Fitbit Charge 3 review.

2. Fitbit Versa

Fitbit Versa
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  • Reviewed on: 11 March 2019

The best Fitbit smartwatch

While it lacks the built-in GPS of the Ionic, the Fitbit Versa is otherwise identical in features, and is smaller and lighter on the wrist. And, of course, it can still connect with the GPS on your phone. As a smartwatch it can use a growing number of apps (Weather, Starbucks, Runkeeper, Strava and more) as well as on-wrist Fitbit Pay and music storage and control, plus notifications such as Caller ID and texts.

Fitbit Coach offers animated on-screen workouts. It also boasts more designer accessories than the Ionic. While aimed at women (who might find the Ionic too large) the Versa is most definitely a unisex design – although it would take a confident man to wear the Peach/Rose-Gold version.

Read our Fitbit Versa review.

3. Fitbit Flex 2

Fitbit Flex 2
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  • Reviewed on: 10 July 2017

The best Fitbit for beginners

The Fitbit Flex 2 is the slimmest, lightest and (let’s face it) least expensive Fitbit wristband. It has a minimalist display of four dots, and (like the Fitbit Versa and Ionic) can track your swimming stats. It doesn’t boast all the features found on others (there’s no altimeter for measuring floors climbed, heart-rate monitor, clock or multi-sports tracking) but if you’re mainly interested in entry-level fitness metrics such as steps, distance and calories, the Flex 2 is a great start for activity tracking.

Via extra accessories, you can also wear it as a fashionable bangle or pendant. But if you want a clock and smart notifications you’ll need to spend a little more.

Read our Fitbit Flex 2 review.

4. Fitbit Ionic

Fitbit Ionic
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  • Reviewed on: 21 March 2019

The best Fitbit for sports

The Fitbit Ionic is the most fully featured Fitbit smartwatch and activity tracker. It has it all, and its built-in GPS is great for runners or exercisers who don’t want to lug their phone around with them.

As well as all the usual fitness stats it features automatic multi-sports tracking, Fitbit Coach for on-screen workouts, Caller ID and texts notifications on wrist, can store up to 300 songs with music control and be used for contactless payments, as well as chose from a range of special apps (Weather, Starbucks, Runkeeper, Strava, and more).

The Fitbit Versa (which has the same features minus the built-in GPS) is cheaper and smaller, but the Ionic is still lightweight enough for you not to realise you’re wearing it.

Read our Fitbit Ionic review.

5. Fitbit Alta HR

Fitbit Alta HR
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  • Reviewed on: 21 November 2018

The best Fitbit for fashion

While in no way restricted to women, the slim, chic and stylish Fitbit Alta HR has the largest selection of wristbands and other fashionable accessories. It’s also a very able activity tracker – measuring steps, distance, active minutes, calories burned, heart rate, sleep stages, and cardio-fitness levels.

Its heart-rate monitor means you’ll get deeper insights into your exercise and sleep monitoring, and so is worth the extra £30/$20 on the less-able Fitbit Alta. We also prefer its watch-type buckle to the pop-clasp of the Alta.

Read our Fitbit Alta HR review.

6. Fitbit Ace

Fitbit Ace
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  • Reviewed on: 21 November 2018

The best Fitbit for kids

Until recently children under 13 were not allowed to have a personal Fitbit account. Now the minimum age is 8 – as long as you use the Fitbit Ace, which measures Steps, Distance and Active Time, plus basic sleep monitoring. Special family account features mean kids (and parents) can track their basic activity stats through a secure Kid View, where they can see their progress, compete in challenges, and earn badges.

The Ace is about exercise not just weight loss – Fitbit hides the calorie counter to stop children obsessing about their weight. The strap is small but you can add accessories meant for the Fitbit Alta, on which it’s based. Older kids might prefer a Fitbit that does more, such as measure heart rate.

Read our Fitbit Ace review.

7. Fitbit Alta

Fitbit Alta
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  • Reviewed on: 29 June 2018

The cheapest Fitbit with a proper display

The only great thing we can say about the Fitbit Alta is that it’s £30/$20 cheaper than the equally stylish Fitbit Alta HR. But that price difference does make it appealing, and – despite lacking the HR’s heart-rate monitor and better sleep-quality and cardio-fitness level tracking – the super-slim Alta is a decent fitness tracker with as many fashion accessories as the more able HR.

We do prefer the Alta HR’s watch-type strap buckle, though, so look out for online deals on the HR first.

Read our Fitbit Alta review.

Which Fitbit is best for you?

Here's a brief function summary, before we go into more detail about features, price, battery life and more. 

  Ace  Flex 2 Alta Alta HR Charge 3 Versa Ionic
RRP £79.99 £69.99 £99.99 £129.99 £129.99 £199.99 £279.99
Shop at Fitbit Buy Buy Buy Buy Buy Buy Buy
Steps, Calories & Distance Y Y Y Y Y Y Y
Floors Climbed - - - - Y Y Y
Clock/Time Y - Y Y Y Y Y
Sleep Tracking & Silent Alarm Y Y Y Y Y Y Y
Sleep Stages (Light, Deep, REM) - - - Y Y Y Y
SmartTrack - Y Y Y Y Y Y
Reminders To Move Y Y Y Y Y Y Y
Swim-proof - Y - - - Y Y
Multi-Sport Tracking - - - - Y Y Y
PurePulse Heart Rate - - - Y Y Y Y
Cardio Fitness Level - - - Y Y Y Y
Onscreen Workouts - - - - - Y Y
Built-in GPS - - - - - - Y
Connected GPS - - - - Y Y -
Call & Text Notifications Calls Y Y Y Y Y Y
Calendar Alerts - - Y Y Y Y Y
Popular Apps - - - - - Y Y
Stores Music - - - - - Y Y
Makes Payments - - - - - Y Y
Music Control - - - - - Y Y
Guided Breathing Sessions - - - - Y Y Y
Fitbit Accessories Y Y Y Y Y Y Y
Designer Accessories - Y Y Y - Y -

Fitbit features compared

The cheap clip-on Zip that we didn't include in our chart lacks the sleep tracking and silent wake alarm found on the other trackers. And it doesn't buzz when you hit your Steps goal. It also doesn't feature a heart-rate monitor, or the sports functions and notification alerts. And in some countries it's no longer available from the Fitbit Store, so we presume it's nearing its end.

For kids below the age of 13, the Ace is a superior starter tracker. It's recommended for children aged 8 up, and there are special Parent and Kid views, plus family challenges and virtual badges to be won. Its strap is smaller than even the Small size options with the other trackers, but we found the other Fitbits fit a child's wrist just as well.

The Ace can be customised with straps for the Alta and Alta HR. While it's in Fitbit's terms and conditions that children aged under 13 should use only the Ace, there are plenty of kids out there wearing other models - parents just need to set-up the child's account using an older birth year.

The cheapest Fitbit wristband is the Flex 2, but this lacks some features of the more expensive Fitbits, such as an altimeter to measure floors climbed, multi-sport functions, heart rate, Caller ID, text notifications and GPS tracking. But casual users don't really need the heart-rate monitor or sports capabilities, and only the top-end Ionic actually boasts a built-in GPS anyway.

The Alta is one step up from the Flex 2, but quite a jump in terms of price. For the extra money you gain a proper screen, plus Caller ID and Text Notifications that many will find very useful. If your phone is a short distance from you but not in your pocket or in Silent mode then that little vibration alert that a call is incoming can be super handy. The Alta is a good deal if the heart monitor and in-depth sleep tracking aren't important to you.

If you do jog, run or exercise in any way as well as walking we think that it's worth paying for the extra heart-rate-monitoring functionality you get with the Alta HR, Charge 3, Versa and Ionic. Monitoring heart rate can also be used if weight loss is one of your key goals. But if you're just interested in everyday exercise the Fitbit Flex 2 or Alta will suffice, and are excellent trackers. The heart-rate function also gives you much more detailed Sleep analysis - see further on for more details of this increasingly important health metric.

We also prefer the watch-buckle strap found on the Alta HR, Charge 3, Versa and Ionic. It feels more secure, and again is worth the paying extra for. If you want a wide range of straps and other accessories the Flex 2 has the most options, including a bangle and pendant, but the Alta, Alta HR and Versa also boast a large array of accessories, and you get plenty of options with the Charge 3 and Ionic.

Remember to factor in the cost of the straps and accessories to the price of the wristband trackers if you fancy something different to the included Classic bands. Having a choice of straps is appreciated, but it does make the pricing harder to compare.

If you're looking for weight tracking, then check out our Fitbit Aria 2 review. These scales sync with the trackers to add measurements of your weight. There are also other good smart scales to buy

Which Fitbit trackers have certain features?

All Fitbits have an accelerometer that measures motion patterns to determine your calories burned, distance travelled, and steps taken. (The Fitbit Ace does not show calories burned, as Fitbit doesn't want to add to a child's possible weight anxiety issues.)  All but the Zip also monitor sleep quality.


The Flex 2, Ace, Alta, Alta HR, Charge 3, Versa and Ionic also contain a vibration motor, which allows it to vibrate when alarms are set to go off. 

Floors climbed

The Charge 3, Versa and Ionic boast an altimeter that measures stairs (or height) climbed. Despite its name, the Alta does not include an altimeter.


The Fitbit Ionic boasts eight sensors, and is the only model in the lineup to have GPS built in without the need for a smartphone to be linked. Users can see distance, pace and elevation climbed, and review routes and split times. The Charge 3 and Versa can connect to the GPS on your smartphone.

Heart-rate monitor

The Alta HR, Charge 3, Versa and Ionic monitor your heart rate on your wrist. They use Fitbit's PurePulse technology that gives continuous, automatic, wrist-based heart rate, plus simplified heart-rate zones.

Additionally the Charge 3, Versa and Ionic feature Cardio Fitness Level, which provides a snapshot of your cardiovascular fitness. Based on estimated VO2 Max – calculated by your user profile, heart rate and exercise data – you can see how your fitness level relates to others of the same age and gender, and get guidance on how to improve over time.

The Charge 3, Versa and Ionic can also monitor the amount of oxygen in the blood (an important health indicator) with their Sp02 sensor.

Caller ID and text messages

The Ace, Charge 3, Alta, Alta HR, Versa and Ionic will all show Caller ID when linked to a smartphone. All the wristbands except the Flex 2 and the Ace also display text notifications on its display, and the Versa and Ionic allow you to control your music from the touchscreen display - each being able to store up to 300 songs on the watch. 

Automatic sport recognition

The Alta, Alta HR, Charge 3, Versa and Ionic feature multi-sport exercise tracking. They know when you're cycling, running, hiking or playing sports including football, tennis and basketball. They will also recognise aerobic workouts such as Zumba, cardio-kickboxing and dance workouts, and log the workout in the Fitbit app along with an exercise summary.

SmartTrack automatically recognises and records workouts and captures all of the stats: how long you were active, calories burned and heart rate zones. By default, it recognises activities when you’ve been moving for more than 15 minutes. You can change this to anywhere from 10 to 90 minutes.

Reminder to Move

This is available on all the wristband Fitbit trackers. It encourages you to meet a mini-step goal of 250 steps each hour (approximately 2-3 minutes of walking). These prompts can be personalised to your schedule; for example, they can be put on “Do Not Disturb” during long meetings or appointments. And, of course, they won't wake you at night.

It's a great motivator to get up and move around, even if just for a stroll to get a glass of water or make a cup of tea. Studies have linked excessive sitting with being overweight and obese, type 2 diabetes, some types of cancer, and early death - I bet that made you sit up...

Sleep tracking

All the Fitbits, except the Zip, check your sleep, too. They measure the time you spend asleep and check the quality of sleep – noting when you are restless or wake up during the night. Fitbit's newer Sleep Stages measurements (on Alta HR, Charge 3, Versa, and Ionic) utilise heart-rate variability to estimate the amount of time you spend in Light, Deep and REM sleep, as well as time awake each night, to better understand your sleep quality.

This is one of the great benefits of a tracker with a heart monitor, and sleep is now recognised as a major health metric. I actually look at this more than some of the other more obvious fitness metrics. Six to eight hours a day is the recommended amount of sleep you should be aiming for. Improved sleep has immediate benefits to your memory, attention, cognitive function, and decision-making capacity, as well as helping to avoid type 2 diabetes and putting on weight. Sleep deprivation causes our appetite to go up and we feel less full, making weight gain more likely.

Sleep can make us happier, improve heart health, boost memory, even reduce the risk of dementia. it is vital for restoring energy levels, washing out toxins from the brain and boosting the immune system.

Relax Guided Breathing

The Charge 3, Versa and Ionic offer Relax Guided Breathing sessions that can help calm your body and mind through two- and five-minute sessions personalised to your breathing rate. The benefits of guided breathing practice are supposed to help reduce stress and anxiety, as well as lower blood pressure. Add it to your daily routine, and you'll quickly feel the benefits. Long-term insulin resistance (caused by stress triggering the brain’s hypothalamus readying your body for action) contributes to the development of type 2 diabetes and obesity, so even light meditation has physical as well as mental benefits to our health.

Which Fitbit has the best display?

The Zip display has five modes: Steps; Distance; Calories burned; Fitbit Smiley (highlights your recent activity level); and Clock.

Fitbit Zip display modes

The Flex 2’s display is the most minimal, consisting of a series of flashing dots that show you how your day is stacking up against your goals. Each light represents 20 percent of your goal. You just tap the display twice to see your progress against your daily goal.

Fitbit Flex 2 display

The Fitbit Alta and Alta HR take a longer, vertical view of its displays, and show much more information than the Flex 2.

Fitbit Alta displays

The Fitbit Ace shows the same stats as the Alta, minus Calories Burned.

Fitbit Ace active minutes

The Charge 3's OLED display (below) shows Time; Steps; Heart Rate; Distance; Calories burned; Floors climbed; Very active minutes; Caller ID; Text Notification; and Alarm.

Fitbit Charge 3 display screens

The Versa's colourful touchscreen display is even better for visual display of fitness stats.

Fitbit Versa screens

The Ionic's larger display (below) shows even more data to fitness and sports nuts. Like the Versa, its display is a touchscreen colour LCD. You can choose from 17 different clock faces, and watch (and listen to) guided exercise workout training sessions.

Ionic screens

Which Fitbit has the best battery life?

The Zip is easily the best for battery life but you will need to buy a new battery two or three times a year. The 3V coin (CR 2025) battery is cheap, though – you can buy a pack of five for under £2.50 (US$3). The other models have rechargeable batteries. Here's roughly how long each lasts between charges:

Zip: 4-6 months

Flex 2: up to 5 days

Ace: up to 5 days

Alta: up to 5 days

Alta HR: up to 7 days

Charge 3: Up to 7 days

Versa: up to 4 days

Ionic: Up to 5 days (will reduce depending on use of GPS)

Which Fitbits are water resistant?

The Flex 2, Charge 3, Versa and Ionic trackers are officially sanctioned as waterproof (down to 50M), and have basic swimming tracking features (number of lengths, distance swam). Experts recommend that you don't wear it while bathing, snorkelling or scuba diving, and Fitbit calls them water resistant rather than properly waterproof. (Note that accessory straps on the Versa and Ionic might not all be waterproof.)

The Zip is just splash proof, while the Alta and Alta HR are water resistant to 1 ATM (Atmosphere), so theoretically can be submerged up to 10 metres (33ft), but Fitbit recommends you remove these trackers even in the shower.

Do all Fitbits use the same app?

Yes. They all use the same iPhone, Android and Windows Phone apps.

The app displays all your daily and historical stats in beautiful graphs that expand in landscape orientation as well as display in portrait view. It's here that Fitbit really beats its activity-tracking rivals.

The desktop dashboard is another visually attractive and informative place to monitor your activity and fitness statistics.

And as an incentive you can link with friends, family and colleagues to compete against each other on the leaderboard, get involved in daily or weekly Challenges and Adventures, and win badges determined by passing goals, and historical milestones. These aspects of the Fitbit system really set it apart from the other trackers.

Fitbit mobile app