Google Pixel Watch 4 45mm vs Xiaomi Watch S4 Sport
Size, specs & wrist fit compared
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Which one fits you
On wrists narrower than about 49mm, the Google Pixel Watch 4 45mm is the safer pick — it stays proportionate down to roughly 47mm, where the Xiaomi Watch S4 Sport starts to hang over the edge. Above 49mm both sit cleanly, and the Xiaomi Watch S4 Sport gives you more presence.
The Xiaomi Watch S4 Sport wears larger than the Google Pixel Watch 4 45mm (46.9mm 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 49g, case only).
Among the 385 45mm watches we hold thickness for, the Google Pixel Watch 4 45mm is thinner than 71%, so it wears flatter than its width suggests.
The Xiaomi Watch S4 Sport is middle-of-the-pack for thickness among the 108 47mm watches in the database.
The Xiaomi Watch S4 Sport is 1.9mm wider, 1.9mm longer, 0.3mm thicker and 12.3g heavier than the Google Pixel Watch 4 45mm. Both are circular.
Pixel Watch 4 - 45mm
Xiaomi
Watch S4 Sport
Switch or add watches
Pixel Watch 4 - 45mm
Xiaomi
Watch S4 Sport
Watch Fit Tool
For sports watches, lug-to-lug (L2L) is what matters most — it decides whether a watch overhangs your wrist. Bulky is fine; overhang is not.
Measure at the point where you wear your watch — typically just below the wrist bone.
Flat width — lay your arm on a table, palm facing up, and measure straight across the top of your wrist with a ruler. Bone to bone; do not follow the curve down the sides.
Around — wrap a tape measure snugly round the wrist. No tape? Wrap a strip of paper, mark the overlap and hold the strip against a ruler.
Width ≠ circumference. They are different numbers — around 170mm is about 64mm across — so set the toggle to whichever one you actually measured before you type it in.
Google Pixel Watch 4 - 45mm
Case 45.0mm · Lug-to-lug 45.0mm · Thickness 12.3mm · 37g
Balanced Fit
45mm on a 55mm wrist
Comfortably inside the edges of your wrist, and it seats and sits low enough to wear without thinking about it.
On a 55mm wrist the sweet spot is 47–53mm lug to lug. This one is 45mm, so you could go bigger.
Measure where you wear it, just below the wrist bone. Either of these works — the tool converts between them.
- 1. Flat width — arm flat on a table, palm up. Measure straight across the top of the wrist, bone to bone, ignoring the curve down the sides.
- 2. Around — a tape, or a strip of paper marked and held against a ruler, snug the whole way round.
Leather: Attaches at the lugs, so the case back rests on your skin. Thins and softens with wear. Typical figures, not this model’s own.
Show the measurementsHide the measurements
- Across the wrist5.0mm spare each side
Comfortable, with visible skin either side.
- Off the wrist12.3mm off the skin
Normal sports-watch height for a wrist this size. (12.3mm case, back against the skin)
- How it seats~5.2mm under the rim
Seats well, with the case back following most of the wrist.
- Weight on the wrist37g
Light enough to forget you have it on. (0.7g per mm of wrist)
Xiaomi Watch S4 Sport
Case 46.9mm · Lug-to-lug 46.9mm · Thickness 12.6mm · 49g
Sweet Spot
46.9mm on a 55mm wrist
Across the wrist it works — 4.1mm spare each side — but wide enough that the edge of the case back lifts clear of the skin.
On a 55mm wrist the sweet spot is 47–53mm lug to lug. This one is 46.9mm, so you could go bigger.
Measure where you wear it, just below the wrist bone. Either of these works — the tool converts between them.
- 1. Flat width — arm flat on a table, palm up. Measure straight across the top of the wrist, bone to bone, ignoring the curve down the sides.
- 2. Around — a tape, or a strip of paper marked and held against a ruler, snug the whole way round.
Leather: Attaches at the lugs, so the case back rests on your skin. Thins and softens with wear. Typical figures, not this model’s own.
Show the measurementsHide the measurements
- Across the wrist4.1mm spare each side
Fills the wrist without reaching the edge.
- Off the wrist12.6mm off the skin
Normal sports-watch height for a wrist this size. (12.6mm case, back against the skin)
- How it seats~6.1mm under the rim
Wide enough that the edge of the case back lifts clear of the skin.
- Weight on the wrist49g
Light enough to forget you have it on. (0.9g per mm of wrist)
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
- Xiaomi Watch S4 Sport46.9mm · 12.6mm thick
3D preview
Google Pixel Watch 4 - 45mm vs Xiaomi Watch S4 Sport 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 Xiaomi Watch S4 Sport lasts 9.4× as long as the Google Pixel Watch 4 45mm (15 days against 38.4 hours).
Google Pixel Watch 4 45mmXiaomi Watch S4 Sport
Smartwatch
1.6 days15 daysBattery Saver
72 hours—
Specifications
The short version
10 key specs| Spec | GooglePixel Watch 4 - 45mm | XiaomiWatch S4 Sport |
|---|---|---|
| Case Width | 45mm | 46.9mm |
| Thickness | 12.3mm | 12.6mm |
| Weight | 36.7g | 49g |
| Shape | Circular | Circular |
| Water Resistance | 5 ATM | 5 ATM |
| GPS | Yes | Yes |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Screen size | 1.4 inches | 1.43 inches |
| Battery life | 1.6 days | 15 days |
| Released | 2025 | 2024 |
Every specification
116 specs| Spec | Google Pixel Watch 4 - 45mm | Xiaomi Watch S4 Sport |
|---|---|---|
| Design | ||
| width | 45 | 46.9 |
| height | 45 | 46.9 |
| volume | 24.91 cm³ | 27.72 cm³ |
| weight | 36.7 g | 49 g |
| thickness | 12.3 | 12.6 |
| ATM rating | 5 ATM | 5 ATM |
| resolution | 456 x 456 px | 466 x 466 px |
| screen size | 1.4 inches | 1.43 inches |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Has a display | Yes | Yes |
| pixel density | 320 ppi | 326 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 | 40 m |
| Watch band is replaceable | Yes | Yes |
| Has sapphire glass display | No | Yes |
| Ingress Protection (IP) rating | IP68 | — |
| has branded damage-resistant glass | Yes | No |
| width of band | — | 22 mm |
| is designed for kids | — | No |
| Battery | ||
| charge time | 1.25 hours | — |
| battery life | 1.6 days | 15 days |
| battery power | 455 mAh | 586 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 | — |
| 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 | — |
| release date | 2025-08-20 | 2024-07-19 |
| Has a stopwatch | Yes | Yes |
| Has smart alarm | No | No |
| warranty period | 1 years | 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 | No |
| Locates your phone | Yes | Yes |
| has fall detection | Yes | No |
| 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 | No |
| has fast/slow heart rate notifications | Yes | Yes |
| Has a built-in camera remote control function | Yes | Yes |
| has a front camera | — | No |
| number of microphones | — | 1 |
| 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) | — |
| supports Wi-Fi | Yes | No |
| supports Galileo | Yes | Yes |
| Bluetooth version | 6 | 5.2 |
| has a cellular module | Yes | Yes |
| Is compatible with iOS | No | Yes |
| 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 |
| App & Software | ||
| Ad-free | Yes | Yes |
| Free app | Yes | Yes |
| Has coaching | Yes | No |
| Includes maps | Yes | Yes |
| Supports routes | Yes | No |
| 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 | No |
| Provides activity reports | Yes | Yes |
| Displays fertile window notifications | Yes | — |
| Counts how many calories you've burned | Yes | 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 | Yes |
| Has a route tracker | Yes | Yes |
| Has exercise tagging | Yes | Yes |
| Has multi-sport mode | No | — |
| 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).
Xiaomi Watch S4 Sport
Sits best on wrists ~49–67mm wide (≈ 13.1–17.9cm circumference).
Frequently Asked Questions
Is the Google Pixel Watch 4 45mm bigger than the Xiaomi Watch S4 Sport?
The Xiaomi Watch S4 Sport is bigger — 46.9mm vs 45mm case width.
Which fits a smaller wrist better, the Google Pixel Watch 4 45mm or the Xiaomi Watch S4 Sport?
The Google Pixel Watch 4 45mm suits wrists around 47–64mm wide, and the Xiaomi Watch S4 Sport around 49–67mm. 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 Xiaomi Watch S4 Sport 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.