• Fitbit Charge 4

  • Fitbit Versa 2

  • How We Tested

  • Which Fitbit is Right for You?

  • Other Fitbits We Tested

  • More Articles You Might Enjoy

Fitbit Charge 3
Credit: Reviewed / Betsey Goldwasser
Best Overall
Fitbit Charge 4

The Charge 4 is our hands-down favorite fitness tracker for its mix of good looks, easy-to-navigate device menus and companion app, and plethora of activity- and sleep-tracking info.

The setup is a cinch for getting the device and app up and running. Once in use, the Charge 4 makes itself known, with hourly reminders to move and a 250-step countdown to hit before you sit back down. The Charge 4, like the other Fitbits we tested, also automatically detects sustained activity, based on the movement patterns and heart-rate data the watch records, giving you credit for it in the app. Walks, runs, and bike rides especially are chronicled pretty accurately within a minute, plus or minus. (Though it’s not foolproof: a vigorous laundry folding session could give you credit for “sport.”)

If you prefer not to rely on the device to automatically recognize your workouts, you can turn on an exercise mode, selecting from seven on the watch that you pre-set from about 15 options on the app. The Charge 4 has built-in GPS, as opposed to its predecessor’s “connected GPS,” which requires you to bring your connected smartphone along if you want mapping and more accurate paces for your walks, runs, and bike rides. The Charge 4’s GPS worked well on my test runs and bike rides, recording distance measurements on par with the Garmin Forerunner 245 running watch against which I tested it. However, the Charge 4 has a small screen that’s hard to read in the sunlight and takes a split-second to wake up (and turns off almost as quickly), making it difficult, if not frustrating, to scope your stats mid-workout. For that reason, I recommend that dedicated runners who want to eyeball their pace, distance, or duration as they run consider a dedicated running watch instead.

Fitbit offers an extensive and active community centered around step-focused challenges, something that no other fitness-tracker company has had the same success replicating. Having a social aspect to help you set and meet goals can be a driving factor for sticking to your wellness plans, and the community is a selling point for Fitbit fans. (During our testing, Google announced it was acquiring Fitbit, which has raised privacy concerns regarding how the tech giant might use all health data accumulated from its vast network. It's something we're keeping an eye on.)

The Charge 4’s sleep tracking seems to record accurately, and as a troubled sleeper, I noticed it captured my middle-of-night restlessness better than some other devices. I also liked perusing the deeper data on resting heart rate (which I suspect is accurate), and time spent in deep and REM sleep (though without a sleep lab analysis, I can’t speak to that accuracy). It also records a Pulse Ox measurement during sleep, which could flag a dip in blood-oxygen level to bring to your doctor’s attention if you suspect you may suffer from sleep apnea.

Which brings up another point about accuracy—namely, that of the Charge 4’s optical heart rate monitor. As a rule, wrist-taken heart rate will never be as accurate to the second as data measured by a chest heart-rate strap by virtue of its distance from the heart. It is fine for tracking trends (such as keeping a record of average resting heart rate), but I’ve never had much success using it for measuring changes in exertion while training, and especially Fitbit’s technology in particular. With the Charge 4, Fitbit unveiled heart rate zone training alerts, which can only be as useful as the data is accurate. Unfortunately, in my experience, it’s just not.

The Charge 4 offers some additional user-friendly health features, including a breathing activity for stress reduction, menstrual cycle tracking, a hydration log, a food log with a searchable database of common foods, as well as pay-to-play workout, meditation, and other wellness programs through the Premium app upgrade.

The Charge 4 has some smartphone features, including notifications, which you can customize or turn off entirely if all that buzzing gets on your nerves. You may reply to texts from the watch using preset canned replies and emojis, but if you want voice-to-text to reply in your own words, you should consider the Versa 2 or another smartwatch.

For a similar range of features (minus built-in GPS) with a larger screen, the Fitbit Versa Lite may be your pick (see below). In general, though, we think most people will prefer the smaller overall size of the Charge 4, particularly for sleeping, despite the compromise to the display.


  • Comprehensive activity tracking features

  • Easy-to-use companion app

  • Comfortable to wear


  • Heart rate monitoring is unreliable during workouts

Fitbit Versa 2 on wrist
Credit: Reviewed / Betsey Goldwasser
Best Upgrade
Fitbit Versa 2

For a smartwatch-like wearable that packs all the great fitness-tracking benefits of Fitbit, the Versa 2 is worth considering if its higher retail price is in your budget. I spent about a month wearing the Versa 2, which has all the activity tracking capabilities of the Charge 4 (minus built-in GPS), plus some very cool next-level features, powered by Amazon Alexa.

Thanks to a large watch face, Versa 2 displays more detail on-screen than Charge 4, though it records the same details about your daily activity, from step count to sleep log. It, too, automatically detects walking, running, biking, and other exercise that’s sustained for a few minutes, or you may turn on a workout mode from the six options on the device to record your sweat session with more precision. Versa 2 includes connected GPS (rather than a built-in chip) for mapping walks or runs, but I found this doesn’t work as well as my dedicated running watch. Curiously, despite being water-resistant, Versa 2 doesn’t have swim tracking, which Charge 4 has. On the other hand, the Versa 2 offers access to Fitbit’s pay-to-play wellness and exercise programs—some of which display prompts to follow on its full-color screen—which are not available on Charge 4. Some users may thrive on that additional guidance to work toward their goals.

What makes the Versa 2 experience that much richer as a “smart” device is the inclusion of Alexa, which allows you to use a number of smartwatch features through voice commands. As an Android phone owner, my favorite function is the ability to reply to text messages using voice-to-text (unfortunately, not an option for iPhone users). Alexa on the Versa 2 also lets you ask for a weather report and even ask random questions you otherwise might pull out your phone to Google. Alexa can control smart home devices and can also be used to control your music, including Spotify and Pandora. Versa 2 also supports Fitbit’s apps, which so far are limited to only a handful of well-known ones (Starbucks, Strava, and the subscription-based New York Times among them), but with Google’s announced acquisition of Fitbit, that may soon change—as will the privacy concerns surrounding Fitbit’s massive trove of health data.


  • Comprehensive activity tracking

  • Long battery life

  • Built-in Alexa and voice commands


  • Limited smartwatch features and apps

  • No GPS

  • Fitbit OS needs work

Related content

How We Tested

The Tester

As a managing editor at Reviewed, I oversee our health and fitness coverage, and as a multi-certified fitness pro, I have a vested interest in providing product recommendations that actually get people moving and making better lifestyle choices, rather than encouraging them to buy into the latest fad that will end up collecting dust or shoved in the back of a drawer. I believe a fitness tracker to be that sort of good-idea purchase, provided it’s actually worn and the wearer buys into the idea that “step count” as a measure of activity level is a valuable motivator to get off their duffs and move more. (While I’d love to turn the world into gym rats or marathoners, I’m not alone in thinking committing to just moving more is the best gateway into fitness—the U.S. government agrees with me.)

The Tests

In our broader fitness tracker tests, our four testers in our Cambridge, Mass. office tested Fitbits (along with trackers from other brands) over the course of four weeks—at that time, we included the Fitbit Charge 3, identical in form and nearly all functions to the newer Charge 4. They wore the devices in pairs on the same wrist for the first few days of each week, taking notes on the setup, look, and feel of the devices and apps. They compared the data each recorded for step count, sleep, and other activity to compare against each other and against the reality of what they did, in terms of how much they walked or exercised and how much they slept. For the remainder of the week, they chose one device of those two to test more extensively, wearing it 24/7. In the meantime, I did my own in-the-weeds assessments of the Versa 2. With the subsequent launch of the Charge 4, I dug into the built-in GPS and heart rate features to see how (or if) they upgraded the Charge 3.

The testers responded to an extensive survey, which asked them to rate everything from the setup to the comfort of the watches themselves when worn 24/7 to the ease of finding health data in the companion apps. We based our rankings on how easy and enjoyable the device was to use, wear, and integrate the information captured into improving one’s activity and sleep habits. We based our rankings of the top Fitbits on how easy and enjoyable each device was to use and wear, and for the user to integrate the information captured into improving one’s activity and sleep habits.

Which Fitbit is Right for You?

Fitbit, more so than Garmin or any other fitness tracker company, has created an unparalleled community of health-minded, step-counting enthusiasts who love a good social challenge as a means to stay on track or even up their fitness game.

Activity tracking-wise, you’ll get more or less the same technology for counting steps, automatically recording bouts of prolonged activity, and measuring sleep duration in any Fitbit you choose (though the one device that lacks heart rate won’t provide as much detail of your sleep). Some Fitbit devices also include GPS, either by connecting to your phone’s location services or directly to the satellites themselves. This can be useful for more accurately recording distances traveling on a walk, run, or bike ride (that is, when it works).

The main differentiators come in terms of the nonactivity features. First, there’s the display type (full color or black-and-white) and size, with some being slim for the band-style devices and others being larger for the watch-style devices. Second, there’s the smartwatch functions—the more basic devices only display notifications (often with text messages truncated), while the higher-end ones allow more interaction and additional apps.

Fitbit features comparison chart
Credit: Reviewed/Naidin Concul-Ticas

Other Fitbits We Tested

Fitbit Versa Lite Edition

The Fitbit Versa Lite is more like a large-screened Charge 4 than the smartwatch-like Versa 2. It has similar activity-tracking guts to our top pick Charge 4, though it has connected GPS—rather than built-in—and (inexplicably) lacks stairs climbed and swim tracking, despite being water-resistant. Along with the larger display, you get access to the Fitbit smartwatch apps, including Strava, Pandora, and scaled-down versions of Yelp and the New York Times (with a subscription)—but without Versa 2’s Alexa, you only get the same canned text messages replies. One of our testers preferred the large, square-ish display over the narrower one of the Charge 4, but others thought the Versa Lite felt large, and one got annoyed at the screen flashing brightly when she was trying to sleep (a do-not-disturb option is buried in the app and watch menu to eliminate that frustration).


  • Large, easy-to-read display

  • Feature-packed fitness tracking

  • Some smartwatch apps


  • Lacks swim tracking and built-in GPS

  • May feel large on some wrists

  • Limited smartwatch features

Fitbit Inspire HR

The budget-minded Fitbit Inspire HR was designed by the company initially for use in its partnerships with corporate wellness programs, and to me it shows: It’s noticeably plasticy and cheap-looking, with a ho-hum monochrome display. Still, if all you want is a simple Fitbit device for tracking the basics on its superior app, and that includes no-reply phone and text notifications, it’ll do. An even less expensive version of the Inspire without heart rate and connected GPS is also available, which can be fine for step-count and fitness purposes—but without the heart rate, you lose out on the deeper data in the sleep tracking.


  • Tracks basic activity well

  • Gets you into the Fitbit universe on a budget


  • Cheap-looking, plastic-y feel

  • Dim display

Fitbit Ionic

To me, it’s a wonder this three-years-old Fitbit Ionic smartwatch, which our previous fitness tracker tester reviewed, is still in the company’s lineup. As near as I can tell, the only reason it hung around is that until the Charge 4, it was the sole Fitbit with an on-board GPS chip for tracking runs, rather than the others, which rely on a connection to your phone for geolocation purposes. Our previous tester found it bulky, uncomfortable, and not intuitive to use. If you want a good running watch, get a Garmin. If you want a Fitbit smartwatch, get the Versa 2.


  • Large display

  • Simple interface

  • Preloaded with a few apps


  • Bulky fit

  • Limited smartwatch capabilities

  • Seems out of date now

Meet the tester

Amy Roberts

Amy Roberts

Managing Editor, Lifestyle and Emerging Categories


At Reviewed, Amy edits and writes articles on health, beauty, fitness, fashion, pets, and more. Previously, she worked for Wirecutter, Good Housekeeping, Refinery29, Men's Fitness, Women's Health, among other print and online publications. She holds a journalism degree from Northwestern University.

See all of Amy Roberts's reviews

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