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How accurate is Fitbit Ionic calorie burn – find review & price?

How accurate is Fitbit Ionic calorie burn

Fitbit Ionic is most popular to fitness lovers as it gives you data on how much calorie you take and how much you burn after certain activity. The Ionic sports GPS, continuous heart rate-monitoring, guided workouts in the new Fitbit Coach app, swim-tracking, and a run-detect feature that turns on GPS and starts tracking your stats when you’ve been running for 2-5 minutes. You don’t have to select a workout or press any buttons; it happens automatically. How accurate is Fitbit Ionic calorie burn?

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Pros & Cons – Fitbit Ionic

  • Accurate and insightful sleep analysis
  • Fitbit Pay works well
  • Bright, clear screen
  • Long battery life
  • Music storage
  • Quick and easy mobile payments
  • Sleek design
  • Up to four-day battery life


  • Controversial design
  • Little bit slow
  • Design
  • Touch screen sometimes unresponsive
  • No always-on display
  • Limited music offering

Fitbit Ionic Smartwatch GPS Price

The Fitbit Ionic launched as the most expensive wearable yet from Fitbit. At £299.95 / $299.95 / AU$449.95 it cost more than the Fitbit Surge running watch did at launch, but a bit less than products like the Apple Watch 5 or Samsung Galaxy Watch Active 2. But how accurate is Fitbit Ionic calorie burn?

Since the launch of the cheaper Fitbit Versa and Fitbit Versa 2, we’ve seen the price drop some way to around $180 / £200 / AU$350 at certain times of year.

How accurate is Fitbit Ionic calorie burn?

A 2017 study published in the Journal of Personalized Medicine found that Fitbit Surge model had about a 27% margin of error, the lowest margin of error among the seven devices tested. 

Other similar devices in the study — including the Apple Watch, PulseOn, and Samsung Gear S2  Basis Peak, Microsoft Band, and Mio Alpha 2 — had higher error rates, up to as high as 93%, rendering them more inaccurate when it comes to calculating calories burned.

How accurate is Fitbit Ionic calorie burn – How does it calculate?

How does a Fitbit calculate the calories you’ve burned? The answer is the use of both specific information about you, and more general calculations pre-loaded into its algorithm, including calculations about how human beings burn calories writ large.

First, you input a number of metrics about yourself into the Fitbit app. These include your age, weight, height, and gender, data points that are used to establish a basal metabolic rate. This, your BMR, is the rate at which you burn calories while at rest (thanks to digestion, your heartbeat, breathing, etc.).

This base rate usually accounts for half the calories reported burned during the day; the rest come from an increased burn the Fitbit assumes you are enjoying when it senses an elevated heart rate and/or motion. But that heart rate could be stress, and the motion could be from a bumpy ride in a vehicle or a nervous tick, so always take Fitbit calorie counts with a grain or three of salt.

How accurate is Fitbit Ionic calorie burn – estimated calorie burnt for activities?

Users reported below calorie burnt estimation –

A slow walk | 255 calories/hour

brisk walk | 391 calories/hour

Hiking | 546 calories/hour

Running 5 mph | 755 calories/hour

Run the stairs | burn 819 calories per hour.

Running, 8 mph | 1,074 calories/hour

Bowling or Dancing; fitboarding | 273 calories/hour

easy cycling | 364 calories/hour

spinning/exercise bike | 550 calories/hour

Jump rope | 1,074 calories/hour  -like running in place but with step count

How to Use the Fitbit Ionic Calorie Counter?

The Fitbit apps for iOS, Android, and Windows include a calorie-counting feature, which lets you manually log food consumed throughout the day. This feature combines with the calorie burned feature to show you how many calories you’re consuming compared to how many calories you’ve burnt throughout the day.

To add Fitbit calorie counting to your app dashboard, go to Discover > Health & Fitness Stats > Food > Add to Today.

Fitbit Ionic Review 2021


The body of the watch is made of aluminum and features very small antenna bands on the sides, but it’s attractive and is easily the best-looking Fitbit product so far. There’s one hardware button on the left-hand side with another two on the right that sit in similar positions to those on the Fitbit Blaze and enable you to move around the watch’s UI.


It has rectangular design, unlike the more square Apple Watch or most Android Wear watches, but it is reminiscent of the Blaze’s screen. This one is quite a bit bigger though, and that’s down to the bezels being thinner.

The watch is 38.6mm wide, but the 349 x 250, color, LCD touch-screen display takes up just 29.7mm of that width. The rest is black bezel, which is thicker on the chin where Fitbit put its logo. 


There are leather and plastic strap options available with secure fasteners on each so the Ionic won’t fall off when you’re out for a jog. The plastic option is comfortable for when you’re sweating in the gym, while the leather strap is a much more attractive look – so you might want to get both if you want to wear this watch both for working out and dining out.


The resolution of the LCD screen is 384 x 250, and we particularly like how bright it is – it reaches 1000 nits, which is the same as the Apple Watch 2 and means you can view it even in bright sunlight when out on a run.


The Ionic’s cross-platform support of both iPhones ($390 at Amazon) and Android phones also allows it to be something I could wear and use with any friend or family member to compete in fitness challenges. Fitbit’s app is still my current favorite for overall fitness logging. Its charts and goals are clearly presented, there are tons of tools and connected apps it works with, and Fitbit’s social network is probably the best around: it taps into fitness challenges, groups interested in particular health goals, and odds are you have plenty of friends to connect with. The Apple Watch’s social fitness functions are slowly growing, but nowhere near as vibrant.

The Ionic comes with its own App Gallery – Fitbit is insistent this isn’t an app store – that includes Fitbit’s own services as well as third-party apps. So far we’ve seen third-party apps from Strava, Starbucks, Philips Hue, The New York Times, Flipboard, Yelp and more.

It’s still a limited set of apps compared to watchOS, Wear OS and even Tizen, but we hope to see the App Gallery expand further especially now the Fitbit Versa supports these too.


You can also upload music to the Fitbit Ionic, with 2.5GB of free space at your disposal. That’s not much, and will only allow for around 300 songs, but if you have particular audiobooks, podcasts or albums you’re always going back to there should be space for some of them here.

Heart rate

More than that, though, there’s an improved PurePulse heart-rate monitor and a new relative SpO2 sensor that can measure blood oxygen levels. The latter is a future-proofing sensor more than anything, as it could lead to the ability to offer a deeper insight into the user’s health and even detect sleep apnoea and arterial fibrillation.

Fitbit claims that the heart-rate monitor is more accurate, partly because of the more stable point of contact as the sensor lights are flush at the back. This is especially important during exercise when the tracker is in more energetic motion.


New features for running include an automatic pause option, which will notice when, for example, you’ve stopped to cross at some traffic lights and pause your workout, then restart when you begin exercising again.

Fitbit has also included workouts in its Fitbit Coach feature that is accessible from the watch and will offer a similar service to the Fitstar app you can download on your phone.


The Ionic is water-resistant for up to 50 meters (same as the Apple Watch) and has a lap-swim workout option in the Exercise app. I worked out with the Ionic in a pool and can attest to its water-resistance, although I am the world’s slowest swimmer and can’t vouch for the accuracy of the device’s lap counts.

Sleep tracking

Like the Charge 2 and Alta HR before it, the Ionic uses your heart rate to graph your sleep cycles, so you can see how much time you spend in REM, light or deep sleep each night. The sleep and wake times are accurate, and the Ionic can also sense when you wake during the night. So, when you sync the device to the Fitbit app in the morning, it can tell you how restless your sleep was.

Battery life

Fitbit Ionic’s battery lasted between four and five days with limited usage. If you’re going to be working out a lot with the watch it’ll be a lot less, and the battery gets hit especially hard when using GPS.

Fitbit estimates it lasts for 10 hours of constant GPS tracking, and we think that’s about right  – and it’s still around the same amount of time as your average running watch is able to last for.

Fitbit payment

Fitbit also put an NFC chip in the Ionic, which means you can store a card on the watch to make purchases. The payment process is just as seamless on the Ionic as it is on the Apple Watch. You press and hold the Ionic’s left-side button near the payment terminal, and it immediately processes the transaction.

How accurate is Fitbit Ionic calorie burn – customer review

Excellent fitness smart watch and tracker!

After having my Ionic for nearly a week and putting it through its paces, I can say it’s helped me retire my Apple Watch Series 3 on certain features that I look for in something that I want to wear every day to work, to the gym, and everywhere in between.

Starting with the things I like about this watch: (1) it’s stylish to a fault, looking nice while also not as eye catching as other brands of smart watches; (2) it’s very comfortable and not intrusive when you want to wear it to bed and track your sleep cycle like my previous Alta HR was; (3) it’s battery life last beyond five days or more, depending on how often you work out; and (4) it does just about everything you want in a fitness tracker, and coupled with the Fitbit app, it’s the best kind of fitness tracker there is.

For the things I don’t like about this watch are: (1) it’s OS is a little slow and not intuitive as the competition (a lot of button presses or swipes to get to certain features; (2) wish there was some voice command similar to Siri; (3) would benefit from a touch-to-wake feature instead of having to press a button or raise your wrist to your face to activate the screen; and (4) not using a universally acceptable charger such as USB-C, micro, and etc.

These are all minor gripes about the design choices Fitbit has made and I believe they are only going to get better over time with each iteration of their Versa and Iconic line. Despite these small shortcomings, everything else Fitbit does, they do it very well in tracking sleep, nutrition, water, heart rate, weight, and so much more.

It’s almost the perfect smart watch, but without some other features that are usually found on either Android or iOS, it’s definitely the best fitness tracker you can buy foremost, but comes in second place when it comes to actual smart watch functions such as having a digital assistant, voice command, and the like. You have to do everything manually to access common features.

Things will only get better every year. Fitbit has a winner here. They just have to keep innovating and implementing what is already on the market, and then take it a step further.

If you’re on the fence about purchasing an Ionic, don’t be. It’s befitting on the wrist more than all the other Fitbit bands or watches out there. Totally worth the upgrade for built-in GPS, water-proofing, and more. Upgrade today while it’s still on sale!

By MaestroJanks at Best Buy

Alternate of Fitbit Ionic Smartwatch GPS

Fitbit Versa

Coming almost six months after the Ionic, the Fitbit Versa has a lower price than this watch and comes with lots of the same features. The design is a touch smaller, so if you don’t want a behemoth taking over your wrist, the Versa may be made for you.

The biggest difference is there’s no GPS on the Fitbit Versa. That means you’ll need to go running with your smartphone to be able to track your location by connecting your watch up and using the Connected GPS tech.

Apart from that, there’s a lot to love from the Fitbit Versa and it may be worth you taking a look at our review before you dive into buying the Ionic.

Apple Watch 4

The latest wearable from Apple, the Watch 4 is its most accomplished smartwatch yet with LTE connectivity to allow you to use it truly without your phone. 

That’s something the Fitbit Ionic can’t offer either, so if you want to be able to go running without your phone and still receive phone calls you may want to opt for Apple’s watch instead. The Apple Watch 3 is also worth considering and is more in line with the price of the Fitbit Ionic.

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