To get the most out of your Fitbit, you want to wear it as much as possible. This means all day at work, all night when you're sleeping, and on every trip to the gym. Make sure your Fitbit is super comfortable around your wrist by following one of their sizing guides before buying. We recommend the Fitbit Versa for most people.

Products used in this guide

Why do you need to measure your wrist before buying a Fitbit?

Fitbit Charge HR

Fitbits come in two standard sizes, small and large (though you can get an X-large by ordering models through the Fitbit site). It's a little strange that there's not a medium or regular size. Does that mean your normal-sized wrist is actually a large? How small is small? How large is large?

Fortunately, Fitbit breaks down wrist sizes based on their circumferences (the distance around the outside of your wrist) and ties those with the different product sizes. This makes it easy to buy a Fitbit and know that it will fit your wrist properly, even if you can't try it on.

What do you need to measure your wrist?

Fitbit actually makes it very easy for you to get an accurate wrist measurement so you can be sure the Fitbit you choose will fit properly.

If you have a printer, you can click on the photos below to download individual Sizing Tools customized for the device you're interested in. Just print it out, cut it out, and use it to see which size fits your wrist best.

Fitbit Small Large X Large Sizing Tool Price
Charge 2 5.5"-6.7" 6.7"-8.1" 8.1"-9.3" Sizing $130
Flex 2 5.5"-6.7" 6.7"-8.1" Unavailable Sizing $60
Alta 5.5"-6.7" 6.7"-8.1" 8.1"-9.3" Sizing $100
Alta HR 5.5"-6.7" 6.7"-8.1" 8.1"-9.3" Sizing $120
Ionic 5.5"-6.7" 6.7"-8.1" Unavailable Sizing $250
Versa 5.5"-7.1" 7.1"-8.7" Unavailable Sizing $200
Ace n/a n/a n/a One size $80

If you do not have a printer, don't worry. Find a piece of string, wrap it around your wrist about two fingers below your wrist bone. Once you've done that, measure how long the piece of string is. Once you have that information, you're ready to match your wrist size with a Fitbit band size.

Which Fitbit size matches your wrist size?

Fitbit Blaze

Fitbits come in small and large sizes out of the box. You can also get an X-large size by ordering through the Fitbit website. If you know the circumference of your wrist, you will know which Fitbit size to buy.

Keep in mind that your Fitbit band is slightly adjustable, so you may have a little bit of wiggle room. If you're unsure, it's best to go a size up and then use the Fitbit's adjustable band to tighten it to your wrist.

Overall, you want to keep your Fitbit loose enough that it comfortably slides back and forth on your wrist. For Fitbits with a built-in heart rate monitor, position them about two fingers above your wrist bone.

Try this on for size

Your Fitbit needs to be comfortable to wear, otherwise you won't enjoy using it. Using these tips will ensure you pick up the right Fitbit size for your wrist. From there you can enjoy charting your progress as you achieve your Fitness goals. And because you've sized your Fitbit properly, it won't slide off when you're patting yourself on the back!

Our top equipment picks

Our Pick

Fitbit Versa

The best fitness tracker is also a pretty decent smartwatch.

The Versa combines Fitbit's strength in accurate and useful fitness tracking with an easy-to-use smartwatch interface for notifications and more from your phone. It's the best of both worlds.

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