Garmin Forerunner 570 42mm vs Forerunner 645 Music
Size, specs & wrist fit compared
Which one fits you
Both need much the same wrist: neither overhangs from 15 cm (5.9 in) round, and both are in their sweet spot around 16–18 cm. Wrist size will not decide between these two.
What else differs
- Battery: 10 days for the Forerunner 570 42mm against 7 days for the Forerunner 645 Music in everyday use; 18 hours for the Forerunner 570 42mm against 14 hours for the Forerunner 645 Music with GPS on.
The Forerunner 570 42mm and Forerunner 645 Music share a near-identical 42.4mm case, so on the wrist the difference is thickness and weight.
The Forerunner 645 Music is 0.1mm wider, 0.6mm thicker and 0.2g heavier than the Forerunner 570 42mm.
Forerunner 570 42mm
Forerunner 645 Music
Forerunner 570 42mm or Forerunner 645 Music by wrist size
| Wrist round (mm left each side) | Forerunner 570 42mm≈49mm lug to lug, est. | Forerunner 645 Music≈49mm lug to lug, est. |
|---|---|---|
| 14 cm / 5.5 in | Overhangs (1.9mm over) | Overhangs (1.9mm over) |
| 15 cm / 5.9 in | Overhangs (0.3mm over) | Overhangs (0.3mm over) |
| 16 cm / 6.3 in | Sweet spot (1.3mm) | Sweet spot (1.3mm) |
| 17 cm / 6.7 in | Sweet spot (2.9mm) | Sweet spot (2.9mm) |
| 18 cm / 7.1 in | Balanced (4.5mm) | Balanced (4.5mm) |
| 19 cm / 7.5 in | Balanced (6.1mm) | Balanced (6.1mm) |
| 20 cm / 7.9 in | Balanced (7.8mm) | Balanced (7.8mm) |
Switch or add watches
Garmin
Forerunner 570 42mm
Garmin
Forerunner 645 Music
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Battery life compared
Furthest apart in GPS with music mode, where the 645 Music lasts 1.6× as long as the 570 42mm (14 hours against 9 hours).
570 42mm645 Music
Smartwatch
10 days7 daysGPS only
18 hours—GPS with music
9 hours14 hoursAll systems + multi-band
13 hours—All systems + multi-band with music
8 hours—
More comparisons
2D Dimension Schematics
- Garmin Forerunner 570 42mm 42.4mm × ≈49mm (est.) · 12.9mm thick
- Garmin Forerunner 645 Music 42.5mm × ≈49mm (est.) · 13.5mm thick
3D preview
Forerunner 570 42mm vs Forerunner 645 Music on a wrist
Specifications
The short version
6 key specs| Spec | GarminForerunner 570 42mm | GarminForerunner 645 Music |
|---|---|---|
| Case Width | 42.4mm | 42.5mm |
| Thickness | 12.9mm | 13.5mm |
| Weight | 42g | 42.2g |
| Shape | Circular | Circular |
| Battery life | Smartwatch mode: Up to 10 days GPS-Only GNSS mode: Up to 18 hours SatIQ (AutoSelect) GNSS mode: Up to 14 hours All-Systems GNSS mode + Multi-Band: Up to 13 hours GPS-Only GNSS mode with music: Up to 9 hours SatIQ (AutoSelect) GNSS mode with music: Up to 8 hours All-Systems GNSS mode + Multi-Band with music: Up to 8 hours See Details | Smartwatch Mode: Up to 7 daysGPS mode without music: Up to 14 hoursGPS mode with music: Up to 5 hours |
| Released | 2025 | 2018 |
Where the specifications differ
9 differences| Spec | Garmin Forerunner 570 42mm | Garmin Forerunner 645 Music |
|---|---|---|
| General | ||
| Battery life | Smartwatch mode: Up to 10 days GPS-Only GNSS mode: Up to 18 hours SatIQ (AutoSelect) GNSS mode: Up to 14 hours All-Systems GNSS mode + Multi-Band: Up to 13 hours GPS-Only GNSS mode with music: Up to 9 hours SatIQ (AutoSelect) GNSS mode with music: Up to 8 hours All-Systems GNSS mode + Multi-Band with music: Up to 8 hours See Details | Smartwatch Mode: Up to 7 daysGPS mode without music: Up to 14 hoursGPS mode with music: Up to 5 hours |
| Strap material | silicone | Silicone |
| Product Info | ||
| Main SKU | 010-02970-00 | 010-01863-30 |
| Product ID | 1463821 | 612476 |
| Product Name | Forerunner® 570 - 42mm | Forerunner® 645 Music |
| Release Date | 5/15/2025 | 1/9/2018 |
| Product Variation | Slate Gray Aluminum with Translucent Black/Black Band | With Black Coloured Band |
| Health & Wellness Monitoring | ||
| Sleep | yes (advanced) | Yes (Advanced) |
| Hydration | yes (in Garmin Connect™ and optional Connect IQ™ widget) | Yes (in Garmin Connect™ and optional Connect IQ™ widget) |
The other 16 specifications both list are identical.
Full Garmin Forerunner 570 42mm specifications →Full Garmin Forerunner 645 Music specifications →