Best Smartwatch for Fitness 2025: Expert Buying Guide

Looking for a fitness smartwatch in 2025? The market has exploded with options, and picking the right one genuinely matters if you want something you’ll actually use. I’ve tested most of these watches, and here’s what I think actually matters.

Let’s skip the marketing fluff. Here’s the reality:

Heart rate tracking varies wildly between watches. Some lose the signal during weightlifting; others stay rock-solid. If you’re doing HIIT or anything with arm movement, this matters more than any other single feature. I learned this the hard way after a month of trusting a watch that kept dropping signal during burpees.

GPS matters if you run or bike outside. Single-band GPS works fine in open areas. But tree cover, buildings, and tall canyons will wreck your distance data unless you get dual-frequency GPS. I stopped trusting my old watch on trail runs once I compared it to a chest strap.

Battery life is the boring feature that determines if your watch becomes drawer jewelry. Nothing kills a fitness habit faster than a device that needs charging every day. The Apple Watch is great, but I know people who’ve given up on it because they got tired of the charging routine.

Sensors have gotten ridiculous. SpO2, ECG, skin temperature, blood pressure—some of this is genuinely useful, some is novelty. If you care about sleep, SpO2 and skin temperature actually help. ECG is great if you have heart concerns. Most people don’t need everything.

Ecosystem is real. Apple Watch doesn’t work well with Android. Samsung’s best features only work with Samsung phones. This isn’t just about convenience—some health features literally won’t work outside their ecosystem.

The Watches

Apple Watch Series 10 is the default for iPhone users, and honestly, it earns that spot. The health features are comprehensive, the screen is finally bright enough to read in sunlight, and the new sleep apnea detection actually works (I know people who’ve gotten alerted and followed up with doctors). The trade-off is battery life—you’re charging every day or two. If that bugs you, it will always bug you.

Garmin Fenix 8 is what serious athletes actually use. The battery lasts for literal weeks. The training readiness score is genuinely useful—it told me to take a rest day when I was about to push through fatigue, and I probably would’ve gotten injured if I’d ignored it. The maps are great for running and cycling in new places. It’s expensive, and the interface takes a week to learn. But if you’re training for something, this is the tool.

Samsung Galaxy Watch 7 is the best Android option if you have a Samsung phone. The health sensors are solid, Google integration finally works properly, and the rotating bezel is weirdly satisfying. If you’re not on Samsung, some features feel half-baked.

Fitbit Charge 6 is the value king. Under $150, you get reliable sleep tracking (Fitbit still leads here), decent heart rate monitoring, and enough smartwatch features to check notifications. Battery lasts a week. The trade-off is no app ecosystem—you’re stuck with what Fitbit provides, which is fine for most people.

Apple Watch Ultra 2 exists for a specific person: someone who runs ultras, dives, or does stuff where a regular watch wouldn’t survive. The battery actually lasts for long events. The action button is useful if your hands are cold or muddy. It’s huge. Most people don’t need it.

Garmin Forerunner 965 is for runners who care about form. The running dynamics (ground contact time, vertical oscillation, stride length) tell you things no other watch in this price range can. It’s light, the battery lasts forever, and the maps are excellent. If you just want to track distance and pace, it’s overkill.

Whoop 4.0 isn’t a watch. It’s a band you wear on your arm. No screen means you check everything on your phone. The recovery and strain tracking is genuinely thoughtful—if you’re trying to optimize training load, it works. The subscription costs money forever, which is annoying.

Samsung Galaxy Watch Ultra is Samsung’s rugged option. Titanium case, ridiculous battery life, works with Android. If you need something that survives real abuse, it does. It’s pricey and hard to find.

Choosing

What should you actually buy?

If you’re on iPhone and want one watch for everything: Apple Watch Series 10. Just accept the charging.

If you’re training for something endurance-related: Garmin Fenix 8. The battery and training features are worth the money.

If you want good enough tracking without spending much: Fitbit Charge 6. It does what most people need.

If you’re a runner who wants biomechanical data: Garmin Forerunner 965.

Android users: your choice depends heavily on your phone. Samsung phone = Galaxy Watch 7. Everyone else = less clear, honestly. The Pixel Watch exists but has worse battery.

The “best” watch is the one you’ll actually wear. A fancy Garmin that sits in a drawer is worse than a Fitbit you use every day. Figure out what you’ll actually do with it, then spend accordingly.