Amazfit Active vs Samsung Galaxy Watch8 - LTE · 40mm
Size, specs & wrist fit compared
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Which one fits you
On wrists narrower than about 45mm, the Amazfit Active is the safer pick — it stays proportionate down to roughly 38mm, where the Samsung Galaxy Watch8 - LTE · 40mm starts to hang over the edge. Above 45mm both sit cleanly, and the Samsung Galaxy Watch8 - LTE · 40mm gives you more presence.
The Amazfit Active wears larger than the Samsung Galaxy Watch8 - LTE · 40mm (42.36mm vs 40.4mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
The Samsung Galaxy Watch8 - LTE · 40mm is the slimmer of the two (8.6mm vs 10.75mm), so it slides under a cuff more easily.
On the wrist the Amazfit Active feels lighter (27g vs 30g, case only).
The Amazfit Active is thinner than 87% of the 42mm watches we track and the Samsung Galaxy Watch8 - LTE · 40mm than 83% of the 40mm ones — so both wear flatter than their widths suggest.
The Amazfit Active is 2mm wider, 6.8mm shorter, 2.2mm thicker and 3g lighter than the Samsung Galaxy Watch8 - LTE · 40mm.
Amazfit
Active
Samsung
Galaxy Watch8 - LTE · 40mm
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Amazfit
Active
Samsung
Galaxy Watch8 - LTE · 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.
Amazfit Active
Case 35.9mm · Lug-to-lug 35.9mm · Thickness 10.8mm · 27g
Understated
35.9mm on a 55mm wrist
Well inside your wrist on every measurement — you have room to go a size up if you want more presence.
On a 55mm wrist the sweet spot is 47–53mm lug to lug. This one is 35.9mm, 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 wrist9.6mm spare each side
Comfortable, with visible skin either side.
- Off the wrist10.8mm off the skin
Normal sports-watch height for a wrist this size. (10.8mm case, back against the skin)
- How it seats~2.4mm under the rim
Sits flat on the wrist with contact right across the case back.
- Weight on the wrist27g
Light enough to forget you have it on. (0.5g per mm of wrist)
Samsung Galaxy Watch8 - LTE · 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.
- Amazfit Active42.4mm × 35.9mm · 10.8mm thick
- Samsung Galaxy Watch8 - LTE · 40mm40.4mm × 42.7mm · 8.6mm thick
3D preview
Amazfit Active vs Samsung Galaxy Watch8 - LTE · 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 Amazfit Active lasts 7.0× as long as the Samsung Galaxy Watch8 - LTE · 40mm (14 days against 2 days).
Amazfit ActiveSamsung Galaxy Watch8 - LTE · 40mm
Battery Saver
720 hours—Smartwatch
14 days2 daysTraining
240 hours—GPS
16 hours—
Specifications
The short version
11 key specs| Spec | AmazfitActive | SamsungGalaxy Watch8 - LTE · 40mm |
|---|---|---|
| Case Width | 42.36mm | 40.4mm |
| Lug-to-Lug | 35.9mm | 42.7mm |
| Thickness | 10.75mm | 8.6mm |
| Weight | 27g | 30g |
| Shape | Rectangle | Circular |
| Water Resistance | 5 ATM | 5 ATM |
| GPS | Yes | Yes |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Screen size | 1.75 inches | 1.34 inches |
| Battery life | 14 days | 2 days |
| Released | 2023 | 2025 |
Every specification
121 specs| Spec | Amazfit Active | Samsung Galaxy Watch8 - LTE · 40mm |
|---|---|---|
| Design | ||
| width | 42.36 | 40.4 |
| height | 35.9 | 42.7 |
| volume | 16.35 cm³ | 14.84 cm³ |
| weight | 27 g | 30 g |
| thickness | 10.75 | 8.6 |
| ATM rating | 5 ATM | 5 ATM |
| resolution | 390 x 450 px | 438 x 438 px |
| screen size | 1.75 inches | 1.34 inches |
| Display type | OLED/AMOLED | OLED/AMOLED |
| Has a display | Yes | Yes |
| pixel density | 341 ppi | 327 ppi |
| width of band | 20 mm | 20 mm |
| water resistance | Water resistant | Water resistant |
| Always-On Display | Yes | Yes |
| has a touch screen | Yes | Yes |
| is designed for kids | No | No |
| Watch band is replaceable | Yes | Yes |
| Has sapphire glass display | No | Yes |
| has branded damage-resistant glass | No | No |
| waterproof depth rating | — | 50 m |
| maximum operating temperature | — | 35 °C |
| Ingress Protection (IP) rating | — | IP68 |
| lowest potential operating temperature | — | 0 °C |
| Battery | ||
| charge time | 2 hours | — |
| battery life | 14 days | 2 days |
| battery power | 300 mAh | 325 mAh |
| has wireless charging | No | Yes |
| has a removable battery | No | No |
| battery life with GPS on | 16 hours | — |
| Has a solar power battery | No | No |
| has a rechargeable battery | Yes | Yes |
| battery life in training mode | 240 hours | — |
| battery life in power save mode | 720 hours | — |
| Sensors | ||
| has GPS | Yes | Yes |
| has a compass | Yes | Yes |
| Has a barometer | No | Yes |
| has a gyroscope | No | 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 | ||
| release date | 2023-10-27 | 2025-07-09 |
| 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 | 0.25GB | 32GB |
| Has notifications | Yes | Yes |
| Has ECG technology | No | Yes |
| Locates your phone | Yes | Yes |
| has fall detection | No | Yes |
| has voice commands | No | Yes |
| Acquires GPS faster | Yes | Yes |
| Has vibrating alerts | Yes | Yes |
| number of microphones | 1 | — |
| shows readiness level | Yes | Yes |
| Can be used to answer calls | Yes | Yes |
| measures resting heart rate | Yes | Yes |
| has irregular heart rate warnings | No | Yes |
| has fast/slow heart rate notifications | Yes | Yes |
| Has a built-in camera remote control function | No | Yes |
| RAM | — | 2GB |
| measures VO2 max | — | Yes |
| Connectivity | ||
| has NFC | No | Yes |
| supports ANT+ | No | No |
| supports Wi-Fi | No | Yes |
| supports Galileo | No | Yes |
| Bluetooth version | 5.2 | 5.3 |
| has a cellular module | No | Yes |
| Is compatible with iOS | Yes | No |
| Is compatible with Android | Yes | Yes |
| SIM cards | — | 1 eSIM |
| Wi-Fi version | — | Wi-Fi 4 (802.11n) |
| 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 live tracking | Yes | — |
| Has exercise diary | Yes | Yes |
| Predicts ovulation | 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 |
| 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 | 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 |
| Tracks calorie intake | Yes | Yes |
| Provides sleep reports | Yes | Yes |
| Detects activities automatically | Yes | Yes |
| Has a stroke counter for swimming | Yes | Yes |
| Has multi-sport mode | — | No |
Wrist Fit
Amazfit Active
Sits best on wrists ~38–51mm wide (≈ 10.1–13.6cm circumference).
Samsung Galaxy Watch8 - LTE · 40mm
Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).
Frequently Asked Questions
Is the Amazfit Active bigger than the Samsung Galaxy Watch8 - LTE · 40mm?
The Amazfit Active is bigger — 42.36mm vs 40.4mm case width.
Which fits a smaller wrist better, the Amazfit Active or the Samsung Galaxy Watch8 - LTE · 40mm?
The Amazfit Active suits wrists around 38–51mm wide, and the Samsung Galaxy Watch8 - LTE · 40mm around 45–61mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Amazfit Active and Samsung Galaxy Watch8 - LTE · 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.