Garmin Forerunner 165 vs Vivoactive 6
Size, specs & wrist fit compared
Which one fits you
Under 15.5 cm (6.1 in) round, the Forerunner 165's lugs overhang and the Vivoactive 6's do not; the Vivoactive 6 fills the wrist at 16–17.5 cm, the Forerunner 165 at 16–18 cm.
What else differs
- Battery: about 11 days each in everyday use; 21 hours for the Vivoactive 6 against 19 hours for the Forerunner 165 with GPS on.
The Forerunner 165 is 0.8mm wider and 0.7mm thicker than the Vivoactive 6.
Forerunner 165
Vivoactive 6
Case width
43mm
42.2mm−0.8mm
Thickness
11.6mm
10.9mm−0.7mm
Forerunner 165 or Vivoactive 6 by wrist size
| Wrist round (mm left each side) | Forerunner 165≈49.5mm lug to lug, est. | Vivoactive 6≈48.5mm lug to lug, est. |
|---|---|---|
| 14 cm / 5.5 in | Overhangs (2.2mm over) | Overhangs (1.7mm over) |
| 15 cm / 5.9 in | Overhangs (0.6mm over) | Overhangs (0.1mm over) |
| 16 cm / 6.3 in | Bold (1.1mm) | Sweet spot (1.6mm) |
| 17 cm / 6.7 in | Sweet spot (2.7mm) | Sweet spot (3.2mm) |
| 18 cm / 7.1 in | Sweet spot (4.3mm) | Balanced (4.8mm) |
| 19 cm / 7.5 in | Balanced (5.9mm) | Balanced (6.4mm) |
| 20 cm / 7.9 in | Balanced (7.5mm) | Balanced (8mm) |
Switch or add watches
Garmin
Forerunner 165
Garmin
Vivoactive 6
As an Amazon Associate, WatchFitTool earns from qualifying purchases.
Battery life compared
Forerunner 165Vivoactive 6
Battery saver
20 days21 daysSmartwatch
11 days11 daysGPS only
19 hours21 hoursAll systems
17 hours17 hoursAll systems with music
—8 hours
More comparisons
2D Dimension Schematics
- Garmin Forerunner 165 43mm × ≈49.5mm (est.) · 11.6mm thick
- Garmin Vivoactive 6 42.2mm × ≈48.5mm (est.) · 10.9mm thick
3D preview
Forerunner 165 vs Vivoactive 6 on a wrist
Specifications
The short version
6 key specs| Spec | GarminForerunner 165 | GarminVivoactive 6 |
|---|---|---|
| Case Width | 43mm | 42.2mm |
| Thickness | 11.6mm | 10.9mm |
| Shape | Circular | Circular |
| Display type | AMOLED (optional always-on mode) | AMOLED (optional always-on mode) |
| Battery life | Smartwatch mode: Up to 11 days Battery Saver Smartwatch mode: Up to 20 days GPS-Only GNSS mode: Up to 19 hours All-Systems GNSS mode: Up to 17 hours See Details | Smartwatch mode: Up to 11 days (5 days display always-on) Battery Saver Smartwatch mode: Up to 21 days GPS-Only GNSS mode: Up to 21 hours All-Systems GNSS mode: Up to 17 hours All-Systems GNSS mode with music: Up to 8 hours See details |
| Released | 2024 | 2025 |
Where the specifications differ
5 differences| Spec | Garmin Forerunner 165 | Garmin Vivoactive 6 |
|---|---|---|
| General | ||
| Battery life | Smartwatch mode: Up to 11 days Battery Saver Smartwatch mode: Up to 20 days GPS-Only GNSS mode: Up to 19 hours All-Systems GNSS mode: Up to 17 hours See Details | Smartwatch mode: Up to 11 days (5 days display always-on) Battery Saver Smartwatch mode: Up to 21 days GPS-Only GNSS mode: Up to 21 hours All-Systems GNSS mode: Up to 17 hours All-Systems GNSS mode with music: Up to 8 hours See details |
| Memory/History | 4 GB | 8 GB |
| What You'll Love | ||
| Water rating | 5 ATM | Swim, 5 ATM |
| Pulse Ox blood oxygen | yes (spot-check, during sleep, all day) | yes (spot-check, and optional all-day and in sleep) |
| Battery life (smartwatch mode) | Up to 11 days | Up to 11 days (5 days display always-on) |
The other 14 specifications both list are identical.
Full Garmin Forerunner 165 specifications →Full Garmin Vivoactive 6 specifications →