Samsung
Galaxy Watch6 - Wi-Fi · 40mm vs Galaxy Watch8 - Wi-Fi · 40mm
Size, specs & wrist fit compared
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Which one fits you
On wrists narrower than about 45mm, the Galaxy Watch6 - Wi-Fi · 40mm is the safer pick — it stays proportionate down to roughly 43mm, where the Galaxy Watch8 - Wi-Fi · 40mm starts to hang over the edge. Above 45mm both sit cleanly, and the Galaxy Watch8 - Wi-Fi · 40mm gives you more presence.
The Galaxy Watch8 - Wi-Fi · 40mm wears larger than the Galaxy Watch6 - Wi-Fi · 40mm (40.4mm vs 38.8mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
The Galaxy Watch6 - Wi-Fi · 40mm is thinner than 93% of the 39mm watches we track and the Galaxy Watch8 - Wi-Fi · 40mm than 83% of the 40mm ones — so both wear flatter than their widths suggest.
The Galaxy Watch8 - Wi-Fi · 40mm is 1.6mm wider, 2.3mm longer, 0.4mm thinner and 1.3g heavier than the Galaxy Watch6 - Wi-Fi · 40mm. Both are circular.
Galaxy Watch6 - Wi-Fi · 40mm
Galaxy Watch8 - Wi-Fi · 40mm
Switch or add watches
Samsung
Galaxy Watch6 - Wi-Fi · 40mm
Samsung
Galaxy Watch8 - Wi-Fi · 40mm
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.
Samsung Galaxy Watch6 - Wi-Fi · 40mm
Case 38.8mm · Lug-to-lug 40.4mm · Thickness 9.0mm · 29g
Balanced Fit
40.4mm 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 40.4mm, 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 wrist7.3mm spare each side
Comfortable, with visible skin either side.
- Off the wrist9.0mm off the skin
Sits low enough to disappear under a cuff. (9.0mm case, back against the skin)
- How it seats~3.1mm under the rim
Seats well, with the case back following most of the wrist.
- Weight on the wrist29g
Light enough to forget you have it on. (0.5g per mm of wrist)
Samsung Galaxy Watch8 - Wi-Fi · 40mm
Case 40.4mm · Lug-to-lug 42.7mm · Thickness 8.6mm · 30g
Balanced Fit
42.7mm 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 42.7mm, 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 wrist6.1mm spare each side
Comfortable, with visible skin either side.
- Off the wrist8.6mm off the skin
Sits low enough to disappear under a cuff. (8.6mm case, back against the skin)
- How it seats~3.5mm under the rim
Seats well, with the case back following most of the wrist.
- Weight on the wrist30g
Light enough to forget you have it on. (0.5g per mm of wrist)
2D Dimension Schematics
Every case drawn to scale on a shared centre — from above, and in profile against the wrist.
- Samsung Galaxy Watch6 - Wi-Fi · 40mm38.8mm × 40.4mm · 9mm thick
- Samsung Galaxy Watch8 - Wi-Fi · 40mm40.4mm × 42.7mm · 8.6mm thick
3D preview
Galaxy Watch6 - Wi-Fi · 40mm vs Galaxy Watch8 - Wi-Fi · 40mm 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 Watch8 - Wi-Fi · 40mm lasts 1.6× as long as the Watch6 - Wi-Fi · 40mm (2 days against 30 hours).
Watch6 - Wi-Fi · 40mmWatch8 - Wi-Fi · 40mm
Battery Saver
100 hours—Smartwatch
1.25 days2 days
Specifications
The short version
11 key specs| Spec | SamsungGalaxy Watch6 - Wi-Fi · 40mm | SamsungGalaxy Watch8 - Wi-Fi · 40mm |
|---|---|---|
| Case Width | 38.8mm | 40.4mm |
| Lug-to-Lug | 40.4mm | 42.7mm |
| Thickness | 9mm | 8.6mm |
| Weight | 28.7g | 30g |
| Shape | Circular | Circular |
| Water Resistance | 5 ATM | 5 ATM |
| GPS | Yes | Yes |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Screen size | 1.3 inches | 1.34 inches |
| Battery life | 1.25 days | 2 days |
| Released | 2023 | 2025 |
Every specification
115 specs| Spec | Samsung Galaxy Watch6 - Wi-Fi · 40mm | Samsung Galaxy Watch8 - Wi-Fi · 40mm |
|---|---|---|
| Design | ||
| width | 38.8 | 40.4 |
| height | 40.4 | 42.7 |
| volume | 14.11 cm³ | 14.84 cm³ |
| weight | 28.7 g | 30 g |
| thickness | 9 | 8.6 |
| ATM rating | 5 ATM | 5 ATM |
| resolution | 432 x 432 px | 438 x 438 px |
| screen size | 1.3 inches | 1.34 inches |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Has a display | Yes | Yes |
| pixel density | 453 ppi | 327 ppi |
| width of band | 20 mm | 20 mm |
| water resistance | Waterproof | Water resistant |
| Always-On Display | Yes | Yes |
| has a touch screen | Yes | Yes |
| waterproof depth rating | 50 m | 50 m |
| Watch band is replaceable | Yes | Yes |
| Has sapphire glass display | Yes | Yes |
| Ingress Protection (IP) rating | IP68 | IP68 |
| has branded damage-resistant glass | No | No |
| is designed for kids | — | No |
| maximum operating temperature | — | 35 °C |
| lowest potential operating temperature | — | 0 °C |
| Battery | ||
| charge time | 1.8 hours | — |
| battery life | 1.25 days | 2 days |
| battery power | 300 mAh | 325 mAh |
| has wireless charging | Yes | 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 | 100 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 | Yes | Yes |
| Monitors blood oxygenation levels | Yes | Yes |
| Features | ||
| RAM | 2GB | 2GB |
| CPU speed | 2 x 1.4 GHz | — |
| release date | 2023-07-26 | 2025-07-09 |
| Has a stopwatch | Yes | Yes |
| Has smart alarm | No | No |
| Has call control | Yes | Yes |
| Has silent alarm | Yes | Yes |
| has HRV tracking | No | Yes |
| internal storage | 16GB | 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 |
| number of microphones | 1 | — |
| shows readiness level | No | 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 |
| Connectivity | ||
| has NFC | Yes | Yes |
| Wi-Fi version | Wi-Fi 4 (802.11n) | Wi-Fi 4 (802.11n) |
| supports ANT+ | No | No |
| supports Wi-Fi | Yes | Yes |
| supports Galileo | Yes | Yes |
| Bluetooth version | 5.3 | 5.3 |
| has a cellular module | No | No |
| Is compatible with iOS | No | No |
| Is compatible with Android | Yes | Yes |
| Miscellaneous | ||
| Has passcode | Yes | Yes |
| Has auto pause | Yes | Yes |
| Is compatible with Windows | No | No |
| Is compatible with Mac OS X | No | No |
| has an external memory slot | No | No |
| Compatible with smart scales | Yes | Yes |
| has a battery level indicator | Yes | Yes |
| has a socket for a 3.5 mm audio jack | No | No |
| Compatible with external heart rate monitors | Yes | Yes |
| App & Software | ||
| Ad-free | Yes | Yes |
| Free app | Yes | Yes |
| Tracks BMI | Yes | Yes |
| Has coaching | Yes | Yes |
| Includes maps | Yes | Yes |
| Supports routes | Yes | Yes |
| Has achievements | Yes | Yes |
| Has goal setting | Yes | Yes |
| Has exercise diary | 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 |
| Provides activity reports | Yes | Yes |
| Counts how many calories you've burned | Yes | Yes |
| Can be personalised | — | Yes |
| Activity tracking | ||
| Measures pace | Yes | Yes |
| Tracks distance | Yes | Yes |
| Tracks elevation | Yes | Yes |
| Designed for golf | No | 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 | Yes | No |
| Tracks calorie intake | Yes | Yes |
| Provides sleep reports | Yes | Yes |
| Detects activities automatically | Yes | Yes |
| Has a stroke counter for swimming | Yes | Yes |
Wrist Fit
Samsung Galaxy Watch6 - Wi-Fi · 40mm
Sits best on wrists ~43–58mm wide (≈ 11.5–15.5cm circumference).
Samsung Galaxy Watch8 - Wi-Fi · 40mm
Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).
Frequently Asked Questions
Is the Samsung Galaxy Watch6 - Wi-Fi · 40mm bigger than the Samsung Galaxy Watch8 - Wi-Fi · 40mm?
The Samsung Galaxy Watch8 - Wi-Fi · 40mm is bigger — 40.4mm vs 38.8mm case width.
Which fits a smaller wrist better, the Samsung Galaxy Watch6 - Wi-Fi · 40mm or the Samsung Galaxy Watch8 - Wi-Fi · 40mm?
The Samsung Galaxy Watch6 - Wi-Fi · 40mm suits wrists around 43–58mm wide, and the Samsung Galaxy Watch8 - Wi-Fi · 40mm around 45–61mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Samsung Galaxy Watch6 - Wi-Fi · 40mm and Samsung Galaxy Watch8 - Wi-Fi · 40mm 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.