Google Pixel Watch 4 - 45mm vs Samsung Galaxy Watch Ultra
Size, specs & wrist fit compared
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Which one fits you
On wrists narrower than about 50mm, the Google Pixel Watch 4 - 45mm is the safer pick — it stays proportionate down to roughly 47mm, where the Samsung Galaxy Watch Ultra starts to hang over the edge. Above 50mm both sit cleanly, and the Samsung Galaxy Watch Ultra gives you more presence.
The Samsung Galaxy Watch Ultra wears larger than the Google Pixel Watch 4 - 45mm (47.4mm vs 45mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
On the wrist the Google Pixel Watch 4 - 45mm feels lighter (36.7g vs 60.5g, case only).
The Google Pixel Watch 4 - 45mm is thinner than 70% of the 45mm watches we track and the Samsung Galaxy Watch Ultra than 86% of the 47mm ones — so both wear flatter than their widths suggest.
The Samsung Galaxy Watch Ultra is 2.4mm wider, 2.4mm longer, 0.2mm thinner and 23.8g heavier than the Google Pixel Watch 4 - 45mm. Both are circular.
Pixel Watch 4 - 45mm
Samsung
Galaxy Watch Ultra
Switch or add watches
Pixel Watch 4 - 45mm
Samsung
Galaxy Watch Ultra
2D Dimension Schematics
Every case drawn to scale on a shared centre — from above, and in profile against the wrist.
- Google Pixel Watch 4 - 45mm45mm · 12.3mm thick
- Samsung Galaxy Watch Ultra47.4mm · 12.1mm thick
3D preview
Google Pixel Watch 4 - 45mm vs Samsung Galaxy Watch Ultra on a wrist
Sized to your own wrist, turned any way you like.
Shapes are built from published measurements, not manufacturer 3D models — accurate proportions, generic dial.
Battery life compared
Furthest apart in Smartwatch mode, where the Samsung Galaxy Watch Ultra lasts 2.5× as long as the Google Pixel Watch 4 - 45mm (4 days against 38.4 hours).
Google Pixel Watch 4 - 45mmSamsung Galaxy Watch Ultra
Battery Saver
72 hours100 hoursSmartwatch
1.6 days4 daysTraining
—48 hours
Specifications
The short version
10 key specs| Spec | GooglePixel Watch 4 - 45mm | SamsungGalaxy Watch Ultra |
|---|---|---|
| Case Width | 45mm | 47.4mm |
| Thickness | 12.3mm | 12.1mm |
| Weight | 36.7g | 60.5g |
| Shape | Circular | Circular |
| Water Resistance | 5 ATM | 10 ATM |
| GPS | Yes | Yes |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Screen size | 1.4 inches | 1.5 inches |
| Battery life | 1.6 days | 4 days |
| Released | 2025 | 2024 |
Every specification
122 specs| Spec | Google Pixel Watch 4 - 45mm | Samsung Galaxy Watch Ultra |
|---|---|---|
| Design | ||
| width | 45 | 47.4 |
| height | 45 | 47.4 |
| volume | 24.91 cm³ | 27.19 cm³ |
| weight | 36.7 g | 60.5 g |
| thickness | 12.3 | 12.1 |
| ATM rating | 5 ATM | 10 ATM |
| resolution | 456 x 456 px | 480 x 480 px |
| screen size | 1.4 inches | 1.5 inches |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Has a display | Yes | Yes |
| pixel density | 320 ppi | 327 ppi |
| water resistance | Waterproof | Waterproof |
| Always-On Display | Yes | Yes |
| has a touch screen | Yes | Yes |
| Gorilla Glass version | Gorilla Glass 5 | — |
| waterproof depth rating | 50 m | 100 m |
| Watch band is replaceable | Yes | Yes |
| Has sapphire glass display | No | Yes |
| Ingress Protection (IP) rating | IP68 | IP68 |
| has branded damage-resistant glass | Yes | No |
| maximum altitude | — | 29527 feet |
| is designed for kids | — | No |
| maximum operating temperature | — | 55 °C |
| lowest potential operating temperature | — | -20 °C |
| Battery | ||
| charge time | 1.25 hours | — |
| battery life | 1.6 days | 4 days |
| battery power | 455 mAh | 590 mAh |
| has wireless charging | No | Yes |
| has a removable battery | No | No |
| Has a solar power battery | No | No |
| has a rechargeable battery | Yes | Yes |
| battery life in power save mode | 72 hours | 100 hours |
| battery life in training mode | — | 48 hours |
| Sensors | ||
| has GPS | Yes | Yes |
| has a compass | Yes | Yes |
| Has a barometer | Yes | Yes |
| has a gyroscope | Yes | Yes |
| Has a cadence sensor | Yes | No |
| has an accelerometer | Yes | Yes |
| Monitors perspiration | No | No |
| Has a heart rate monitor | Yes | Yes |
| Has a temperature sensor | Yes | Yes |
| Monitors blood oxygenation levels | Yes | Yes |
| Features | ||
| RAM | 2GB | 2GB |
| release date | 2025-08-20 | 2024-07-10 |
| Has a stopwatch | Yes | Yes |
| Has smart alarm | No | No |
| warranty period | 1 years | — |
| Has call control | Yes | Yes |
| Has silent alarm | Yes | Yes |
| has HRV tracking | Yes | Yes |
| internal storage | 32GB | 32GB |
| measures VO2 max | Yes | Yes |
| Has notifications | Yes | Yes |
| Has ECG technology | Yes | Yes |
| Locates your phone | Yes | Yes |
| has fall detection | Yes | Yes |
| has voice commands | Yes | Yes |
| Acquires GPS faster | No | Yes |
| Has vibrating alerts | Yes | Yes |
| shows readiness level | Yes | Yes |
| Can be used to answer calls | Yes | Yes |
| measures resting heart rate | Yes | Yes |
| has irregular heart rate warnings | Yes | Yes |
| has fast/slow heart rate notifications | Yes | Yes |
| Has a built-in camera remote control function | Yes | Yes |
| has a front camera | — | No |
| Connectivity | ||
| has NFC | Yes | Yes |
| SIM cards | 1 eSIM | 1 eSIM |
| Wi-Fi version | Wi-Fi 4 (802.11n), Wi-Fi 5 (802.11ac), Wi-Fi 6 (802.11ax) | Wi-Fi 4 (802.11n), Wi-Fi 5 (802.11ac) |
| supports Wi-Fi | Yes | Yes |
| supports Galileo | Yes | Yes |
| Bluetooth version | 6 | 5.4 |
| has a cellular module | Yes | Yes |
| Is compatible with iOS | No | No |
| Is compatible with Android | Yes | Yes |
| supports ANT+ | — | No |
| Miscellaneous | ||
| Has passcode | Yes | Yes |
| Is compatible with Windows | No | No |
| Is compatible with Mac OS X | No | No |
| has an external memory slot | No | No |
| has a battery level indicator | Yes | Yes |
| has a socket for a 3.5 mm audio jack | No | No |
| Has auto pause | — | Yes |
| Compatible with smart scales | — | Yes |
| Compatible with external heart rate monitors | — | Yes |
| App & Software | ||
| Ad-free | Yes | Yes |
| Free app | Yes | Yes |
| Has coaching | Yes | Yes |
| Includes maps | Yes | Yes |
| Supports routes | Yes | Yes |
| Has achievements | Yes | Yes |
| Has goal setting | Yes | Yes |
| Has live tracking | Yes | — |
| Has exercise diary | Yes | Yes |
| Predicts ovulation | Yes | Yes |
| Can be personalised | Yes | Yes |
| Has weight tracking | Yes | Yes |
| Predicts start date | Yes | Yes |
| Tracks water intake | Yes | Yes |
| Has inactivity alerts | Yes | Yes |
| Has period notifications | Yes | Yes |
| Has temperature tracking | Yes | Yes |
| Doesn’t require account | No | — |
| Provides activity reports | Yes | Yes |
| Displays fertile window notifications | Yes | Yes |
| Counts how many calories you've burned | Yes | Yes |
| Tracks BMI | — | Yes |
| Activity tracking | ||
| Measures pace | Yes | Yes |
| Tracks distance | Yes | Yes |
| Tracks elevation | Yes | Yes |
| Designed for golf | No | — |
| Tracks your sleep | Yes | Yes |
| Tracks steps taken | Yes | Yes |
| Designed for diving | No | No |
| Has a route tracker | Yes | Yes |
| Has exercise tagging | Yes | Yes |
| Has multi-sport mode | No | Yes |
| Tracks calorie intake | Yes | Yes |
| Provides sleep reports | Yes | Yes |
| Detects activities automatically | Yes | Yes |
| Has a stroke counter for swimming | No | Yes |
Wrist Fit
Google Pixel Watch 4 - 45mm
Sits best on wrists ~47–64mm wide (≈ 12.6–17.1cm circumference).
Samsung Galaxy Watch Ultra
Sits best on wrists ~50–68mm wide (≈ 13.4–18.2cm circumference).
Frequently Asked Questions
Is the Google Pixel Watch 4 - 45mm bigger than the Samsung Galaxy Watch Ultra?
The Samsung Galaxy Watch Ultra is bigger — 47.4mm vs 45mm case width.
Which fits a smaller wrist better, the Google Pixel Watch 4 - 45mm or the Samsung Galaxy Watch Ultra?
The Google Pixel Watch 4 - 45mm suits wrists around 47–64mm wide, and the Samsung Galaxy Watch Ultra around 50–68mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Google Pixel Watch 4 - 45mm and Samsung Galaxy Watch Ultra side by side at true scale?
Yes — the schematics and photos above show both watches at matched scale, and our fit tool overlays each on your wrist width.