Both have solar charging and a MIP display. The fenix costs three times as much.

Short answer

Garmin fenix 8 Solar - 32 GB of maps, Wi-Fi, BeiDou and QZSS, titanium and sapphire. Instinct 3 Solar - up to 40 days, lighter (58 g) and three times cheaper.

Key differences

SpecGarmin fenix 8 47mm SolarGarmin Instinct 3 50mm Solar
Display1.3", MIP, 260×260MIP, 176×176
Memory32 GB128 MB
Battery lifeup to 21 dayup to 40 days
ConnectivityBluetooth, ANT+, Wi-FiBluetooth, ANT+
NavigationGPS, GLONASS, Galileo, QZSS, BeiDouGPS, GLONASS, Galileo
NFCyesyes
Sensorsheart rate, barometer, compass, gyroscope, temperatureheart rate, barometer, compass, gyroscope, temperature
Protection10 ATM10 ATM
CompatibilityiPhone, AndroidiPhone, Android
Dimensions, weight47×47×15.2 mm, 80 g50×50×14.4 mm, 58 g
Pricecurrent pricescurrent prices

Specs come from the device pages on Smartphone.ua.

Storage and maps

32 GB vs 128 MB - only the fenix has topo maps.

Battery life

Up to 21 vs up to 40 days.

What's the same

MIP display, NFC, barometer, 10 ATM.

Verdict: who should buy which

  • Maps and premium materials - Garmin fenix 8 Solar.
  • Battery life and price - Garmin Instinct 3 Solar.

FAQ

Does the Instinct have Wi-Fi?
No.

How heavy are they?
80 and 58 g.

Which is cheaper?
The Instinct 3 Solar.

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