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Fenix 8 47mm Solar vs Fenix 8 51mm Solar

Garmin Fenix 8 47mm Solar vs Garmin Fenix 8 51mm Solar

What Fenix 8 47mm Solar does better (1) and where Fenix 8 51mm Solar wins (6) — every spec side by side.

Garmin · 2024Fenix 8 47mm Solar

6.8Score

1 advantage≈ $1,000

Garmin · 2024Fenix 8 51mm Solar

7.5Score

6 advantages≈ $1,100

Higher score

3.8Display4.4

7.8Battery life9.3

8.3Health tracking8.3

8.2Sports & outdoor8.2

3.2Smart features3.2

7.1Build & durability6.2

Dimensions

Size comparison

Fenix 8 47mm SolarFenix 8 51mm Solar

	Fenix 8 47mm Solar	Fenix 8 51mm Solar	Difference
Height	47 mm	51 mm	−4 mm
Width	47 mm	51 mm	−4 mm
Thickness	15.2 mm	15.4 mm	−0.2 mm
Weight	80 g	95 g	−15 g

Drawn to the same scale from the official dimensions (front and side).

Why is Fenix 8 47mm Solar better than Fenix 8 51mm Solar?

Weight80 g vs 95 g+19%

Why is Fenix 8 51mm Solar better than Fenix 8 47mm Solar?

Battery life (smartwatch mode)21 days vs 30 days+43%
GPS battery life67 h vs 95 h+42%
Screen size1.3″ vs 1.4″+8%
Battery saver mode34 days vs 48 days+41%
GPS battery life (dual-band)37 h vs 52 h+41%
Resolution (width)260 px vs 280 px+8%

Specifications

Side by side

Only differences	Garmin Fenix 8 47mm Solar≈ $1,0006.8	Garmin Fenix 8 51mm Solar≈ $1,1007.5
Design & durability
Case size	47 mm	51 mm
Weight	80 g	95 g
Thickness	15.2 mm	15.4 mm
Height	47 mm	51 mm
Width	47 mm	51 mm
Case material	Titanium	Titanium
Sapphire crystal	Yes	Yes
Lens / cover glass	Power Sapphire ™	Power Sapphire ™
Strap material	silicone	silicone
Water resistance	10 ATM	10 ATM
Water rating (maker)	10 ATM	10 ATM
Rated dive depth	40 m	40 m
Display
Screen size	1.3″	1.4″
Display technology	Memory-in-pixel (transflective)	Memory-in-pixel (transflective)
Panel	Sunlight-visible, transflective memory-in-pixel	Sunlight-visible, transflective memory-in-pixel
AMOLED / OLED display	No	No
Always-on display	Yes	Yes
Touchscreen	Yes	Yes
Resolution (width)	260 px	280 px
Resolution (height)	260 px	280 px
Pixel density	200 ppi	200 ppi
Battery
Battery life (smartwatch mode)	21 days	30 days
Battery saver mode	34 days	48 days
GPS battery life	67 h	95 h
GPS battery life (dual-band)	37 h	52 h
Battery type	Lithium ion	Lithium ion
Solar charging	Yes	Yes
Wireless charging	No	No
Charging	Garmin proprietary plug charger	Garmin proprietary plug charger
Health sensors
Optical heart rate	Yes	Yes
Blood oxygen (SpO2)	Yes	Yes
ECG	Yes	Yes
Skin temperature	Yes	Yes
Temperature sensor	Yes	Yes
HRV tracking	Yes	Yes
Sleep tracking	Yes	Yes
Sensors	GPS, GLONASS, Galileo, QZSS, BeiDou, SatIQ technology, Elevate wrist heart rate monitor, Pulse Ox blood oxygen saturation monitor, Barometric altimeter, Compass, Gyroscope, Accelerometer, Thermometer, Ambient light sensor, Depth sensor	GPS, GLONASS, Galileo, QZSS, BeiDou, SatIQ technology, Elevate wrist heart rate monitor, Pulse Ox blood oxygen saturation monitor, Barometric altimeter, Compass, Gyroscope, Accelerometer, Thermometer, Ambient light sensor, Depth sensor
Sports & navigation
Built-in GPS	Yes	Yes
Dual-band GPS	Yes	Yes
Satellite systems	GLONASS, GALILEO, BDS, QZSS	GLONASS, GALILEO, BDS, QZSS
Offline maps	Yes	Yes
Barometric altimeter	Yes	Yes
Compass	Yes	Yes
Multisport / triathlon mode	Yes	Yes
Sport profiles	99	99
Dive mode	Yes	Yes
LED flashlight	Yes	Yes
Connectivity
NFC payments	Yes	Yes
Wi-Fi	Wi-Fi 4	Wi-Fi 4
ANT+ sensors	Yes	Yes
Smart features
Calls from the wrist	Yes	Yes
Speaker	Yes	Yes
Microphone	Yes	Yes
Voice assistant	Yes	Yes
Music on the watch	Yes	Yes
Storage	32 GB	32 GB
Third-party apps	Yes	Yes
Platform
Operating system	Garmin OS	Garmin OS
Platform	Proprietary	Proprietary
Works with	iOS, Android	iOS, Android