Marketing says every flagship smartwatch does it all. The data says otherwise. We defined a “complete” smartwatch as one that ticks all five of the features buyers ask for most — an ECG, blood-oxygen (SpO₂), skin-temperature sensing, built-in GPS, and a week or more of battery — then checked all 36 watches in our database against it. Only a handful make the cut, and the brands that miss may surprise you.
- ›The complete smartwatch is rare: only 6 of 36 models (17%) tick all five boxes.
- ›Not one is an Apple, Samsung or Google: every “complete” watch is a fitness-first brand. All 9 mainstream models fail — on battery.
- ›Battery is the universal blocker: 0 of 9 Apple/Samsung/Google watches last a week, so no matter how many sensors they pack, they can’t qualify.
- ›The cheapest “does-everything” device isn’t a smartwatch at all — it’s the Fitbit Charge 6, a budget tracker.
- ›Most watches land at 3–4 of 5: 25 of 36 models get close but miss one feature.
Almost complete — but not quite
Plenty of watches get close. The most common outcome is 3 or 4 of the five features: 14 models have four, 11 have three. Getting all five at once is where nearly every watch falls down.
The 6 that do it all — and who’s missing
Here are the 6 watches that tick every box: Amazfit Balance 2, Fitbit Charge 6, Fenix 8, Garmin Enduro 3, Polar Vantage V3, Polar Grit X2 Pro. The striking part is the absence: there is not a single Apple Watch, Galaxy Watch or Pixel Watch on the list.
Why? The mainstream smartwatches have all the sensors — but they run bright always-on displays and full app ecosystems that drain the battery in about a day. 0 of 9 last a week, so they’re disqualified on the one feature that has nothing to do with sensors.
The budget surprise
The single most affordable device that does everything on our list is the Fitbit Charge 6 — a sub-$150 fitness tracker, not a premium smartwatch. It packs an ECG, SpO₂, skin temperature, GPS and a multi-day battery for a fraction of a flagship’s price. Proof that “complete” and “expensive” are not the same thing.
Bonus: how many are actually swim- and dive-ready?
While we were counting, water resistance: 35 of 36 (97%) are rated for swimming (5 ATM / 50 m or better), but only 8 (22%) are built for diving (10 ATM or a dedicated dive rating). “Water resistant” rarely means “take it scuba diving.”
The full scorecard
Every watch in the database, scored against the five features. Sorted by how many they hit. Specs reflect official manufacturer documentation; feature availability can vary by region and software version.
| Smartwatch | ECG | SpO₂ | Temp | GPS | Week+ battery | Complete? |
|---|---|---|---|---|---|---|
| Amazfit Balance 2 Amazfit | Yes | Yes | Yes | Yes | Yes | ✓ Complete |
| Fitbit Charge 6 Fitbit | Yes | Yes | Yes | Yes | Yes | ✓ Complete |
| Fenix 8 Garmin | Yes | Yes | Yes | Yes | Yes | ✓ Complete |
| Garmin Enduro 3 Garmin | Yes | Yes | Yes | Yes | Yes | ✓ Complete |
| Polar Vantage V3 Polar | Yes | Yes | Yes | Yes | Yes | ✓ Complete |
| Polar Grit X2 Pro Polar | Yes | Yes | Yes | Yes | Yes | ✓ Complete |
| Amazfit T-Rex 3 Amazfit | — | Yes | Yes | Yes | Yes | 4/5 |
| Amazfit Active 2 Amazfit | Yes | Yes | — | Yes | Yes | 4/5 |
| Apple Watch Series 10 Apple | Yes | Yes | Yes | Yes | — | 4/5 |
| Apple Watch Ultra 2 Apple | Yes | Yes | Yes | Yes | — | 4/5 |
| Apple Watch Series 11 Apple | Yes | Yes | Yes | Yes | — | 4/5 |
| Apple Watch Ultra 3 Apple | Yes | Yes | Yes | Yes | — | 4/5 |
| Fitbit Sense 2 Fitbit | Yes | Yes | Yes | Yes | — | 4/5 |
| Garmin Instinct 3 Garmin | Yes | Yes | — | Yes | Yes | 4/5 |
| Venu 3 Garmin | Yes | Yes | — | Yes | Yes | 4/5 |
| Huawei Watch GT 5 Huawei | — | Yes | Yes | Yes | Yes | 4/5 |
| OnePlus Watch 3 OnePlus | Yes | Yes | Yes | Yes | — | 4/5 |
| Galaxy Watch 7 Samsung | Yes | Yes | Yes | Yes | — | 4/5 |
| Galaxy Watch Ultra Samsung | Yes | Yes | Yes | Yes | — | 4/5 |
| Withings ScanWatch 2 Withings | Yes | Yes | Yes | — | Yes | 4/5 |
| Amazfit GTR 4 Amazfit | — | Yes | — | Yes | Yes | 3/5 |
| Amazfit Bip 5 Amazfit | — | Yes | — | Yes | Yes | 3/5 |
| COROS Pace 3 COROS | — | Yes | — | Yes | Yes | 3/5 |
| Fitbit Versa 4 Fitbit | — | Yes | Yes | Yes | — | 3/5 |
| Forerunner 165 Garmin | — | Yes | — | Yes | Yes | 3/5 |
| Forerunner 965 Garmin | — | Yes | — | Yes | Yes | 3/5 |
| vivoactive 5 Garmin | — | Yes | — | Yes | Yes | 3/5 |
| Pixel Watch 3 | Yes | Yes | — | Yes | — | 3/5 |
| Galaxy Watch FE Samsung | Yes | Yes | — | Yes | — | 3/5 |
| Suunto Race Suunto | — | Yes | — | Yes | Yes | 3/5 |
| Xiaomi Watch S3 Xiaomi | — | Yes | — | Yes | Yes | 3/5 |
| Fitbit Inspire 3 Fitbit | — | Yes | — | — | Yes | 2/5 |
| Forerunner 55 Garmin | — | — | — | Yes | Yes | 2/5 |
| TicWatch Pro 5 Mobvoi | — | Yes | — | Yes | — | 2/5 |
| Apple Watch SE (2nd gen) Apple | — | — | — | Yes | — | 1/5 |
| Garmin Lily 2 Garmin | — | Yes | — | — | — | 1/5 |
Free to reference with attribution. Suggested citation:
Smartwatch Trends (2026). The Complete Smartwatch: What It Takes to Do Everything. Retrieved from https://smartwatchestrends.com/complete-smartwatch-2026-study/
Want to filter these 36 watches by the exact features you need? Try our free interactive Smartwatch Finder → — or read the companion study on which features are now standard.
Methodology: a watch is “complete” if it has an ECG, SpO₂, skin-temperature sensor, built-in GPS and a stated battery life of 7 days or more (smartwatch mode; “weeks” coded as 21 days). Data from official manufacturer specifications as of August 2026. See our research process.