Garmin Fenix 8 Pro 47mm AMOLED vs Fenix 8 Pro 51mm AMOLED
Size, specs & wrist fit compared
Which one fits you
Under 18 cm (7.1 in) round, the 51mm's lugs overhang and the 47mm's do not; the 47mm fills the wrist at 17.5–19.5 cm, the 51mm at 19 cm and up.
What else differs
- Battery: 27 days for the 51mm against 15 days for the 47mm in everyday use; 3.3 days for the 51mm against 44 hours for the 47mm with GPS on.
Among the 79 smartwatches 47mm across that we hold thickness for, the Fenix 8 Pro 47mm AMOLED is thicker than 97%, so it sits higher on the wrist than most of its size.
The Fenix 8 Pro 51mm AMOLED is 4mm wider, 0.5mm thicker and 13g heavier than the Fenix 8 Pro 47mm AMOLED.
Fenix 8 Pro 47mm AMOLED
Fenix 8 Pro 51mm AMOLED
Case width
47mm
51mm+4mm
Thickness
16mm
16.5mm+0.5mm
Weight
77g
90g+13g
Fenix 8 Pro AMOLED: 47mm or 51mm by wrist size
| Wrist round (mm left each side) | 47mm≈54mm lug to lug, est. | 51mm≈58.5mm lug to lug, est. |
|---|---|---|
| 14 cm / 5.5 in | Overhangs (4.4mm over) | Overhangs (6.7mm over) |
| 15 cm / 5.9 in | Overhangs (2.8mm over) | Overhangs (5.1mm over) |
| 16 cm / 6.3 in | Overhangs (1.2mm over) | Overhangs (3.4mm over) |
| 17 cm / 6.7 in | Bold (0.4mm) | Overhangs (1.8mm over) |
| 18 cm / 7.1 in | Sweet spot (2mm) | Overhangs (0.2mm over) |
| 19 cm / 7.5 in | Sweet spot (3.6mm) | Bold (1.4mm) |
| 20 cm / 7.9 in | Balanced (5.3mm) | Sweet spot (3mm) |
Switch or add watches
Garmin
Fenix 8 Pro 47mm AMOLED
Garmin
Fenix 8 Pro 51mm AMOLED
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Battery life compared
47mm AMOLED51mm AMOLED
Battery saver
19 days34 daysSmartwatch
15 days27 daysExpedition
14 days24 daysMax battery GPS
70 hours123 hoursGPS only
44 hours78 hoursAll systems
34 hours60 hoursAll systems + multi-band
30 hours53 hoursAll systems + multi-band with music
13 hours23 hours
More comparisons
2D Dimension Schematics
- Garmin Fenix 8 Pro 47mm AMOLED 47mm × ≈54mm (est.) · 16mm thick
- Garmin Fenix 8 Pro 51mm AMOLED 51mm × ≈58.5mm (est.) · 16.5mm thick
3D preview
Fenix 8 Pro 47mm AMOLED vs Fenix 8 Pro 51mm AMOLED on a wrist
Specifications
The short version
7 key specs| Spec | GarminFenix 8 Pro 47mm AMOLED | GarminFenix 8 Pro 51mm AMOLED |
|---|---|---|
| Case Width | 47mm | 51mm |
| Thickness | 16mm | 16.5mm |
| Weight | 77g | 90g |
| Shape | Circular | Circular |
| Display type | AMOLED | AMOLED |
| Battery life | Smartwatch: Up to 15 days (8 days always-on) Battery Saver Watch Mode: Up to 19 days GPS Only: Up to 44 hours (33 hours always-on) All Satellite Systems: Up to 34 hours (26 hours always-on) All Satellite Systems + Multi-band: Up to 30 hours (23 hours always-on)* All Satellite Systems + Multi-band + LTE Livetrack: Up to 12 hours (11 hours always-on)* All Satellite Systems + Multiband + Music: Up to 13 hours (13 hours always on)* All Satellite Systems + Multiband + Music + LTE Livetrack: Up to 8 hours (8 hours always on)* Max Battery GPS: Up to 70 hours Expedition GPS: Up to 14 days *Assuming typical use with SatIQ technology | Smartwatch: Up to 27 days (15 days always-on) Battery Saver Watch Mode: Up to 34 days GPS Only: Up to 78 hours (56 hours always-on) All Satellite Systems: Up to 60 hours (47 hours always-on) All Satellite Systems + Multi-band: Up to 53 hours (41 hours always-on)* All Satellite Systems + Multi-band + LTE Livetrack: Up to 21 hours (19 hours always-on)* All Satellite Systems + Multiband + Music: Up to 23 hours (21 hours always on)* All Satellite Systems + Multiband + Music + LTE Livetrack: Up to 15 hours (14 hours always on)* Max Battery GPS: Up to 123 hours Expedition GPS: Up to 24 days *Assuming typical use with SatIQ technology |
| Released | 2025 | 2025 |
Where the specifications differ
6 differences| Spec | Garmin Fenix 8 Pro 47mm AMOLED | Garmin Fenix 8 Pro 51mm AMOLED |
|---|---|---|
| General | ||
| Weight | 77 g (case only: 56 g) | 90 g (case only: 65 g) |
| Battery life | Smartwatch: Up to 15 days (8 days always-on) Battery Saver Watch Mode: Up to 19 days GPS Only: Up to 44 hours (33 hours always-on) All Satellite Systems: Up to 34 hours (26 hours always-on) All Satellite Systems + Multi-band: Up to 30 hours (23 hours always-on)* All Satellite Systems + Multi-band + LTE Livetrack: Up to 12 hours (11 hours always-on)* All Satellite Systems + Multiband + Music: Up to 13 hours (13 hours always on)* All Satellite Systems + Multiband + Music + LTE Livetrack: Up to 8 hours (8 hours always on)* Max Battery GPS: Up to 70 hours Expedition GPS: Up to 14 days *Assuming typical use with SatIQ technology | Smartwatch: Up to 27 days (15 days always-on) Battery Saver Watch Mode: Up to 34 days GPS Only: Up to 78 hours (56 hours always-on) All Satellite Systems: Up to 60 hours (47 hours always-on) All Satellite Systems + Multi-band: Up to 53 hours (41 hours always-on)* All Satellite Systems + Multi-band + LTE Livetrack: Up to 21 hours (19 hours always-on)* All Satellite Systems + Multiband + Music: Up to 23 hours (21 hours always on)* All Satellite Systems + Multiband + Music + LTE Livetrack: Up to 15 hours (14 hours always on)* Max Battery GPS: Up to 123 hours Expedition GPS: Up to 24 days *Assuming typical use with SatIQ technology |
| Physical size | 47 x 47 x 16 mm Fits wrists with the following circumference: Silicone band: 125-208 mm UltraFit Band: 125-215 mm Leather Band: 132-210 mm Metal Band: 132-215 mm | 51 x 51 x 16.5 mm Fits wrists with the following circumference: Silicone band: 127-210 mm UltraFit Band: 127-225 mm Leather Band: 135-213 mm Metal Band: 135-225 mm |
| QuickFit® watch band compatible | included (22 mm) | included (26 mm) |
| Variant | ||
| Case Size | 47 mm | 51 mm |
| What You'll Love | ||
| Battery life (smartwatch mode) | Up to 15 days (8 days always-on) | Up to 27 days (15 days always-on) |
The other 353 specifications both list are identical.
Full Garmin Fenix 8 Pro 47mm AMOLED specifications →Full Garmin Fenix 8 Pro 51mm AMOLED specifications →