Both run Wear OS and both have sapphire. The Xiaomi is big and long-lasting, the Samsung slim and light.

Short answer

Xiaomi Watch 5 - 930 mAh, up to 6 days, 1.54" 480×480. Galaxy Watch8 40 mm - 8.6 mm and 30 g, IP68 and MIL-STD-810H, cheaper.

Key differences

SpecXiaomi Watch 5Samsung Galaxy Watch8 40mm Bluetooth
Display1.54", AMOLED, 480×4801.34", Super AMOLED, 438×438
ChipQualcomm Snapdragon W5 Gen 1Samsung Exynos W1000
Memory2 GB / 32 GB2 GB RAM / 32 GB
Battery lifeup to 6 days—
Battery930 mAh325 mAh
ConnectivityBluetooth, Wi-FiBluetooth, Wi-Fi
NavigationGPS, GLONASS, Galileo, BeiDou, QZSS (L1 + L5)GPS, GLONASS, Galileo, BeiDou (L1 + L5)
NFCyesyes
Sensorsheart rate, SpO2, barometer, compass, gyroscopeheart rate, SpO2, barometer, compass, gyroscope, temperature
Protection5 ATM5 ATM / IP68 / MIL-STD-810H
OSWear OSWear OS 6
CompatibilityAndroid 8.0+ (GMS)Android 12+, Google Mobile Services
Dimensions, weight47×47×12.3 mm, 56 g42.7×40.4×8.6 mm, 30 g
Pricecurrent pricescurrent prices

Specs come from the device pages on Smartphone.ua.

Battery

930 vs 325 mAh - almost three times as much.

Case

47×47×12.3 mm and 56 g vs 42.7×40.4×8.6 mm and 30 g.

Protection

5 ATM vs 5 ATM, IP68 and MIL-STD-810H.

Verdict: who should buy which

  • Battery life and a big screen - Xiaomi Watch 5.
  • Compactness and price - Galaxy Watch8 40 mm.

FAQ

Do they work with an iPhone?
No, both are Android only.

How much storage?
2/32 GB on both.

Which is cheaper?
The Galaxy Watch8.

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