Best fitness trackers for weight loss

The calorie number is the least reliable thing on your wrist. Ignore it, and a tracker can still help.

I haven't worn any of these bands. The product facts come from maker pages, checked on 3 November 2026, and the research is named as I go. A tracker isn't a medical device. It won't tell you what weight is right for you. If you're losing weight for a medical reason, or food has become hard to think about, talk to your GP first.

What trackers actually change

The best summary I read is Ferguson 2022 in Lancet Digital Health, a peer-reviewed review of 39 systematic reviews covering 163,992 people of all ages, healthy and clinical. The authors declare no competing interests. Taken together, those reviews suggested about 1,800 extra steps a day and 40 min more walking, with weight down by about 1 kg.

One kilogram. That's the honest size of it.

The studies pooled there used many different trackers, and the search ended in April 2021, so no band on this page is in it. Treat the result as evidence about wearing a tracker at all.

The trial that went the other way

Jakicic 2016 is the result that should keep you honest. This peer-reviewed randomised trial in JAMA followed 471 adults aged 18 to 35, with a BMI of 25 to under 40, for 24 months, all on a low-calorie diet with more activity and counselling. I read the abstract only, so I haven't checked its funding.

At six months, half added a wearable and half logged diet and activity on a website. After 24 months, the wearable group had lost 3.5 kg on average, and the website group 5.9 kg. Fitness and activity improved in both, with no significant difference.

So a band didn't beat plain logging, and it did worse on weight. That was an older device in a structured programme. Still, I wouldn't buy any of these expecting the band to do the work.

Why the calorie figure misleads

Fuller 2020, a peer-reviewed review of 158 publications and nine brands, put it flatly: "For energy expenditure, no brand was accurate." Its literature ends in May 2019.

Newer tests haven't rescued it. Lee 2026, peer-reviewed and funded by SOLUM Health Care, which employs one author, tested four wrist devices including the Fitbit Charge 5 and Garmin Vivosmart 5 on 62 healthy men. In resistance exercise, calorie readings correlated with the reference at only r = 0.10 to 0.34.

Fitbit's older models tend to under-read. Chevance 2022, a peer-reviewed meta-analysis, found a pooled -2.77 kcal/min, with individual limits running from -12.75 to 7.41. "Recent" there means as of 2022, so it doesn't cover the Air or the Edge. I found no test of any band on this page against a lab calorie measure. DC Rainmaker (independent, non-peer-reviewed, one wearer, August 2026) only compared them with each other. The Polar Loop often read 50% above the rest and the CIRQA tended low, and he says to allow a margin of error instead of eating to the figure. The Edge wasn't in that test.

So don't eat back what the app says you burned. There's more on this in how accurate calorie counts are.

What to use a band for

Use the numbers that don't need precision. Step counts and active minutes work as a nudge even when they're a little off, since you're comparing yourself with last week.

Here's how I'd set it up. Pick one target, say a daily walk of 30 min, and leave it alone for a month. Look at the weekly trend, skip the daily figure, and turn off anything that shows calories burned, if the app lets you. Weigh yourself on a scale. Your wrist can't do that part.

Then choose by what would stop you wearing it. That's why this list is all bands. They last a week or more on a charge, and three of the four have no screen to look at.

Which band suits which person

If you dislike subscriptions, the Polar Loop is the plain answer. Polar calls it subscription-free. The Fitbit Air and Edge have an optional Google Health Premium plan, and Garmin keeps its coaching behind Connect+.

The Fitbit Air weighs the least. If your problem is that you take things off, start there. Fitbit Air vs Amazfit Helio Strap covers that end of the market.

One warning on availability. I read Google's UK store from outside the UK, so confirm you can get the Air or Edge into a UK basket.

If you walk outdoors and want a route with no phone, only the Edge has GPS of its own. The Fitbit Edge review goes through its sport function.

Not sure a band is the right shape at all? The weight goal page also lists watches, and the picker narrows them by training.