WatchFitTool
Samsung Galaxy Watch8 - LTE · 40mm — case dimensions and design

Samsung · 2025

Galaxy Watch8 - LTE · 40mmSize, Dimensions & Wrist Fit

Case Width

40.4mm

Thickness

8.6mm

Lug-to-Lug

42.7mm

Weight

30g

The Samsung Galaxy Watch8 - LTE · 40mm sits best on flat wrist widths of about 4561mm (≈ 12.016.3cm wrist circumference). Adjust the slider below to check your wrist.

Affiliate disclosure: As an Amazon Associate, WatchFitTool earns from qualifying purchases. If you buy through links on this page, we may earn a commission at no extra cost to you. Learn more.

The Galaxy Watch8 - LTE · 40mm in short

The figures that decide whether this watch suits you, pulled out of the full specification sheet further down.

  • Rated for 2 days of use per charge.
  • Water rated to 50 m.
  • 30g on the wrist. Lighter than 81% of the 40mm watches we have weights for.
  • 1.34 inches OLED/AMOLED display, always-on capable.
  • Takes 20mm bands, so third-party straps fit without an adapter.

Does the Galaxy Watch8 - LTE · 40mm fit your wrist?

Drag the slider to your wrist width and see the Galaxy Watch8 - LTE · 40mm overlaid at true scale. Lug-to-lug — not case diameter — decides whether a watch overhangs your wrist.

Fit tool

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.

Your wrist
mm
≈ 146.9mm around

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

10:09TUE 12lug to lug 42.7mmyour wrist 55.0mm

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 4753mm lug to lug. This one is 42.7mm, so you could go bigger.

How to Measure

Measure where you wear it, just below the wrist bone. Either of these works — the tool converts between them.

  1. 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. 2. Around — a tape, or a strip of paper marked and held against a ruler, snug the whole way round.
Complete Wrist Measurement Guide →
Against one you know

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 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)

Happy with the fit? Check current availability for the Galaxy Watch8 - LTE · 40mm.

Check offer

2D Dimension Schematics

The Galaxy Watch8 - LTE · 40mm drawn to scale — from above, and in profile against the wrist.

Highlight
From above — true scale
From the side — how far it sits off the wrist
  • Samsung Galaxy Watch8 - LTE · 40mm40.4mm × 42.7mm · 8.6mm thick

3D preview

Samsung Galaxy Watch8 - LTE · 40mm on a wrist

On an arm sized to your own wrist — the view a product photo never gives you.

Open 3D try-on

Shapes are built from published measurements, not manufacturer 3D models — accurate proportions, generic dial.

Which Galaxy Watch8 - LTE size fits you?

This model comes in 2 versions. Set your measurement and each one reports its own verdict — tap any size to open its page.

Which of these fits your wrist?

55.0mm

Roughly a 14.7cm wrist circumference — the measurement a tape gives you. Compared against lug-to-lug where we have it, case width otherwise.

All 2 Galaxy Watch8 - LTE variants fit this wrist. The 43.7mm · LTE gives you the most presence without overhanging; the smallest is the discreet end of the range.

40.4mm · LTEViewing
Balanced Fit
Width
40.4mm
Thick
8.6mm
Weight
30g

6.1mm clear a side

43.7mm · LTEBest fit
Balanced Fit
Width
43.7mm
Thick
8.6mm
Weight
34g

4.5mm clear a side

View this size

Galaxy Watch8 - LTE · 40mm battery life

The runtime the manufacturer publishes for everyday use.

  • Smartwatch2 days

How the Galaxy Watch8 - LTE · 40mm ranks on battery

Against the 64 Samsung watches in our database, ranked on each figure Samsung publishes.

  • Everyday use2 days#20 of 64
  • Capacity325 mAh#32 of 64
See all 64 Samsung watches ranked by battery life

What size band does the Galaxy Watch8 - LTE · 40mm take?

Lug width

20mm

Any 20mm strap fits, so you are not restricted to Samsung's own bands. Quick-release pins let you swap without tools — check that a replacement lists 20mm and quick-release before buying.

Affiliate disclosure: As an Amazon Associate, WatchFitTool earns from qualifying purchases. If you buy through links on this page, we may earn a commission at no extra cost to you. Learn more.

Galaxy Watch8 - LTE · 40mm specifications

The figures that decide a purchase, followed by every line Samsung publishes.

Battery life
2 days
Display
1.34 inches
Resolution
438 x 438 px
Water rating
5 ATM
Strap
20 mm
Storage
32GB

Full specification sheet

112 published lines across 8 groups, unedited

Design

width
40.4
height
42.7
volume
14.84 cm³
weight
30 g
thickness
8.6
ATM rating
5 ATM
resolution
438 x 438 px
screen size
1.34 inches
Display type
OLED/AMOLED
Has a display
pixel density
327 ppi
width of band
20 mm
water resistance
Water resistant
Always-On Display
has a touch screen
is designed for kids
waterproof depth rating
50 m
Watch band is replaceable
Has sapphire glass display
maximum operating temperature
35 °C
Ingress Protection (IP) rating
IP68
has branded damage-resistant glass
lowest potential operating temperature
0 °C

Battery

battery life
2 days
battery power
325 mAh
has wireless charging
has a removable battery
Has a solar power battery
has a rechargeable battery

Sensors

has GPS
has a compass
Has a barometer
has a gyroscope
Has a cadence sensor
has an accelerometer
Monitors perspiration
Has a heart rate monitor
Has a temperature sensor
Monitors blood oxygenation levels

Features

RAM
2GB
release date
2025-07-09
Has a stopwatch
Has smart alarm
Has call control
Has silent alarm
has HRV tracking
internal storage
32GB
measures VO2 max
Has notifications
Has ECG technology
Locates your phone
has fall detection
has voice commands
Acquires GPS faster
Has vibrating alerts
shows readiness level
Can be used to answer calls
measures resting heart rate
has irregular heart rate warnings
has fast/slow heart rate notifications
Has a built-in camera remote control function

Connectivity

has NFC
SIM cards
1 eSIM
Wi-Fi version
Wi-Fi 4 (802.11n)
supports ANT+
supports Wi-Fi
supports Galileo
Bluetooth version
5.3
has a cellular module
Is compatible with iOS
Is compatible with Android

Miscellaneous

Has passcode
Has auto pause
Is compatible with Windows
Is compatible with Mac OS X
has an external memory slot
Compatible with smart scales
has a battery level indicator
has a socket for a 3.5 mm audio jack
Compatible with external heart rate monitors

App & Software

Ad-free
Free app
Tracks BMI
Has coaching
Includes maps
Supports routes
Has achievements
Has goal setting
Has exercise diary
Can be personalised
Has weight tracking
Predicts start date
Tracks water intake
Has inactivity alerts
Has period notifications
Has temperature tracking
Provides activity reports
Counts how many calories you've burned

Activity tracking

Measures pace
Tracks distance
Tracks elevation
Designed for golf
Tracks your sleep
Tracks steps taken
Designed for diving
Has a route tracker
Has exercise tagging
Has multi-sport mode
Tracks calorie intake
Provides sleep reports
Detects activities automatically
Has a stroke counter for swimming

Galaxy Watch8 - LTE · 40mm — Frequently Asked Questions

Will the Samsung Galaxy Watch8 - LTE · 40mm fit my wrist?

The Samsung Galaxy Watch8 - LTE · 40mm looks balanced on flat wrist widths of roughly 45–61mm (about 12.0–16.3cm circumference). Drag the slider above to check it against your own measurement.

What size band does the Samsung Galaxy Watch8 - LTE · 40mm take?

20mm. Any 20mm strap fits, so you are not limited to Samsung's own bands — look for a quick-release fitting if you want to swap without tools.

How long does the Samsung Galaxy Watch8 - LTE · 40mm battery last?

Samsung rates it at 2 days per charge in everyday use.

How does the Samsung Galaxy Watch8 - LTE · 40mm battery compare with other Samsung watches?

At 2 days in everyday use it ranks #20 of the 64 Samsung watches in our database — the top 31% of the range. The full ranking, including GPS and power-saving figures, is on our Samsung battery life comparison.

Is the Samsung Galaxy Watch8 - LTE · 40mm thick for a 40mm watch?

At 8.6mm, thinner than 83% of 40mm watches, so it slides under a cuff more easily than most of its size. Thickness, not case width, is what decides whether a watch catches on a shirt cuff.

Should I get the 40.4mm or 43.7mm Galaxy Watch8 - LTE?

The Galaxy Watch8 - LTE comes in 2 case sizes — 40.4mm, 43.7mm. Which one suits you depends on the flat width of your wrist rather than preference: the larger sizes need a wider wrist to sit inside the edge. Set your measurement in the size picker above and each variant reports its clearance in millimetres.

What other watches are the same size as the Samsung Galaxy Watch8 - LTE · 40mm?

TAG Heuer Aquaracer Professional 200 Solargraph 40 UK Limited Edition, Xiaomi Redmi Watch 6, Vivo Watch GT 2 - Bluetooth, Huawei Watch Fit 4 Pro all sit within half a millimetre of the Samsung Galaxy Watch8 - LTE · 40mm's 40.4mm case, so they cover the same amount of wrist.

What is the lug-to-lug of the Samsung Galaxy Watch8 - LTE · 40mm?

42.7mm, against a 40.4mm case width. Lug-to-lug is the measurement that decides overhang: if it exceeds the flat width of your wrist, the lugs sit past the edge no matter how modest the case diameter looks.