Xiaomi Watch S3 eSIM vs Watch S4 Sport
Size, specs & wrist fit compared
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Which one fits you
Both need much the same wrist — roughly 49–67mm across the flat of the wrist. Neither will fit where the other won't, so decide on thickness, weight and features instead.
The Watch S3 eSIM and Watch S4 Sport share a near-identical 47mm case, so wrist presence comes down to thickness, lug-to-lug and weight.
The Watch S3 eSIM is the slimmer of the two (12mm vs 12.6mm), so it slides under a cuff more easily.
On the wrist the Watch S3 eSIM feels lighter (44g vs 49g, case only).
Among the 102 47mm watches we hold thickness for, the Watch S3 eSIM is thinner than 76%, so it wears flatter than its width suggests.
The Watch S4 Sport is middle-of-the-pack for thickness among the 108 47mm watches in the database.
The Watch S3 eSIM is 0.1mm wider, 0.1mm longer, 0.6mm thinner and 5g lighter than the Watch S4 Sport. Both are circular.
Watch S3 eSIM
Watch S4 Sport
Switch or add watches
Xiaomi
Watch S3 eSIM
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.
Xiaomi Watch S3 eSIM
Case 47.0mm · Lug-to-lug 47.0mm · Thickness 12.0mm · 44g
Sweet Spot
47mm on a 55mm wrist
Across the wrist it works — 4.0mm 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 47mm.
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 wrist4.0mm spare each side
Fills the wrist without reaching the edge.
- Off the wrist12.0mm off the skin
Normal sports-watch height for a wrist this size. (12.0mm 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 wrist44g
Light enough to forget you have it on. (0.8g 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.
- Xiaomi Watch S3 eSIM47mm · 12mm thick
- Xiaomi Watch S4 Sport46.9mm · 12.6mm thick
3D preview
Watch S3 eSIM vs 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
Runtime for every power mode either watch publishes, 1 of them directly comparable.
S3 eSIMS4 Sport
Smartwatch
15 days15 daysTraining
3 hours—GPS
3 hours—
Specifications
The short version
10 key specs| Spec | XiaomiWatch S3 eSIM | XiaomiWatch S4 Sport |
|---|---|---|
| Case Width | 47mm | 46.9mm |
| Thickness | 12mm | 12.6mm |
| Weight | 44g | 49g |
| Shape | Circular | Circular |
| Water Resistance | 5 ATM | 5 ATM |
| GPS | Yes | Yes |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Screen size | 1.43 inches | 1.43 inches |
| Battery life | 15 days | 15 days |
| Released | 2023 | 2024 |
Every specification
111 specs| Spec | Xiaomi Watch S3 eSIM | Xiaomi Watch S4 Sport |
|---|---|---|
| Design | ||
| width | 47 | 46.9 |
| height | 47 | 46.9 |
| volume | 26.51 cm³ | 27.72 cm³ |
| weight | 44 g | 49 g |
| thickness | 12 | 12.6 |
| ATM rating | 5 ATM | 5 ATM |
| resolution | 466 x 466 px | 466 x 466 px |
| screen size | 1.43 inches | 1.43 inches |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Has a display | Yes | Yes |
| pixel density | 326 ppi | 326 ppi |
| water resistance | Waterproof | Waterproof |
| Always-On Display | Yes | Yes |
| has a touch screen | Yes | Yes |
| is designed for kids | No | No |
| waterproof depth rating | 50 m | 40 m |
| Watch band is replaceable | Yes | Yes |
| Has sapphire glass display | No | Yes |
| has branded damage-resistant glass | No | No |
| width of band | — | 22 mm |
| Battery | ||
| battery life | 15 days | 15 days |
| battery power | 486 mAh | 586 mAh |
| has wireless charging | No | Yes |
| has a removable battery | No | No |
| battery life with GPS on | 3 hours | — |
| Has a solar power battery | No | No |
| has a rechargeable battery | Yes | Yes |
| battery life in training mode | 3 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 | No | No |
| has an accelerometer | Yes | Yes |
| Monitors perspiration | No | No |
| Has a heart rate monitor | Yes | Yes |
| Has a temperature sensor | No | Yes |
| Monitors blood oxygenation levels | Yes | Yes |
| Features | ||
| release date | 2023-10-26 | 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 notifications | Yes | Yes |
| Has ECG technology | No | No |
| Locates your phone | Yes | Yes |
| has fall detection | Yes | No |
| has voice commands | Yes | Yes |
| Acquires GPS faster | Yes | Yes |
| Has vibrating alerts | Yes | Yes |
| number of microphones | 1 | 1 |
| 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 HRV tracking | — | Yes |
| internal storage | — | 32GB |
| measures VO2 max | — | Yes |
| has a front camera | — | No |
| shows readiness level | — | Yes |
| Connectivity | ||
| has NFC | Yes | Yes |
| SIM cards | 1 eSIM | 1 eSIM |
| supports ANT+ | No | No |
| supports Wi-Fi | No | No |
| supports Galileo | Yes | Yes |
| Bluetooth version | 5.2 | 5.2 |
| has a cellular module | Yes | Yes |
| Is compatible with iOS | Yes | Yes |
| Is compatible with Android | Yes | Yes |
| Miscellaneous | ||
| Has passcode | No | 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 | Yes | No |
| Compatible with external heart rate monitors | Yes | — |
| App & Software | ||
| Free app | Yes | Yes |
| Has coaching | Yes | No |
| Supports routes | Yes | No |
| Has achievements | Yes | Yes |
| Has goal setting | Yes | 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 | No | 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 |
| Ad-free | — | Yes |
| Includes maps | — | 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 |
| 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
Xiaomi Watch S3 eSIM
Sits best on wrists ~49–67mm wide (≈ 13.1–17.9cm circumference).
Xiaomi Watch S4 Sport
Sits best on wrists ~49–67mm wide (≈ 13.1–17.9cm circumference).
Frequently Asked Questions
Is the Xiaomi Watch S3 eSIM bigger than the Xiaomi Watch S4 Sport?
The Xiaomi Watch S3 eSIM is bigger — 47mm vs 46.9mm case width.
Which fits a smaller wrist better, the Xiaomi Watch S3 eSIM or the Xiaomi Watch S4 Sport?
The Xiaomi Watch S3 eSIM suits wrists around 49–67mm 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 Xiaomi Watch S3 eSIM 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.