WatchFitTool

Samsung Galaxy Watch6 Wi-Fi 40mm vs Xiaomi Redmi Watch 3 Active

Size, specs & wrist fit compared

Samsung Galaxy Watch6 - Wi-Fi · 40mm
Samsung Galaxy Watch6 - Wi-Fi · 40mm
38.8mm × 40.4mmCheck offerView specs
Xiaomi Redmi Watch 3 Active
Xiaomi Redmi Watch 3 Active
38.9mm × 46.9mmCheck offerView specs

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Which one fits you

On wrists narrower than about 49mm, the Samsung Galaxy Watch6 Wi-Fi 40mm is the safer pick — it stays proportionate down to roughly 43mm, where the Xiaomi Redmi Watch 3 Active starts to hang over the edge. Above 49mm both sit cleanly, and the Xiaomi Redmi Watch 3 Active gives you more presence.

The Samsung Galaxy Watch6 Wi-Fi 40mm and Xiaomi Redmi Watch 3 Active share a near-identical 38.8mm case, so wrist presence comes down to thickness, lug-to-lug and weight.

The Samsung Galaxy Watch6 Wi-Fi 40mm is the slimmer of the two (9mm vs 10.9mm), so it slides under a cuff more easily.

On the wrist the Samsung Galaxy Watch6 Wi-Fi 40mm feels lighter (28.7g vs 42g, case only).

Among the 340 39mm watches we hold thickness for, the Samsung Galaxy Watch6 Wi-Fi 40mm is thinner than 93%, so it wears flatter than its width suggests.

The Xiaomi Redmi Watch 3 Active is middle-of-the-pack for thickness among the 376 39mm watches in the database.

The Xiaomi Redmi Watch 3 Active is 0.1mm wider, 6.5mm longer, 1.9mm thicker and 13.3g heavier than the Samsung Galaxy Watch6 Wi-Fi 40mm.

Samsung

Galaxy Watch6 - Wi-Fi · 40mm

Xiaomi

Redmi Watch 3 Active

Case width
38.8mm
38.9mm+0.1mm
Lug-to-lug
40.4mm
46.9mm+6.5mm
Thickness
9mm
10.9mm+1.9mm
Weight
28.7g
42g+13.3g

Switch or add watches

Samsung Galaxy Watch6 - Wi-Fi · 40mm

Samsung

Galaxy Watch6 - Wi-Fi · 40mm

Xiaomi Redmi Watch 3 Active

Xiaomi

Redmi Watch 3 Active

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 Watch6 - Wi-Fi · 40mm

Case 38.8mm · Lug-to-lug 40.4mm · Thickness 9.0mm · 29g

Balanced Fit

40.4mm on a 55mm wrist

10:09TUE 12lug to lug 40.4mmyour 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 47–53mm lug to lug. This one is 40.4mm, 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 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)

Xiaomi Redmi Watch 3 Active

Case 46.9mm · Lug-to-lug 46.9mm · Thickness 10.9mm · 42g

Sweet Spot

46.9mm on a 55mm wrist

10:09TUE 12lug to lug 46.9mmyour wrist 55.0mm

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.

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 wrist4.1mm spare each side

    Fills the wrist without reaching the edge.

  • Off the wrist10.9mm off the skin

    Normal sports-watch height for a wrist this size. (10.9mm 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 wrist42g

    Light enough to forget you have it on. (0.8g per mm of wrist)

2D Dimension Schematics

Every case drawn to scale on a shared centre — from above, and in profile against the wrist.

Highlight
From above — same centre, true scale
From the side — how far each sits off the wrist
  • Samsung Galaxy Watch6 - Wi-Fi · 40mm38.8mm × 40.4mm · 9mm thick
  • Xiaomi Redmi Watch 3 Active38.9mm × 46.9mm · 10.9mm thick

3D preview

Samsung Galaxy Watch6 - Wi-Fi · 40mm vs Xiaomi Redmi Watch 3 Active on a wrist

Sized to your own wrist, turned any way you like.

Open 3D try-on

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 Redmi Watch 3 Active lasts 9.6× as long as the Samsung Galaxy Watch6 Wi-Fi 40mm (12 days against 30 hours).

Samsung Galaxy Watch6 Wi-Fi 40mmXiaomi Redmi Watch 3 Active

  • Smartwatch

    1.25 days
    12 days
  • Battery Saver

    100 hours
    —

Specifications

The short version

11 key specs
SpecSamsungGalaxy Watch6 - Wi-Fi · 40mmXiaomiRedmi Watch 3 Active
Case Width38.8mm38.9mm
Lug-to-Lug40.4mm46.9mm
Thickness9mm10.9mm
Weight28.7g42g
ShapeCircularRectangle
Water Resistance5 ATM5 ATM
GPSYesNo
Display typeOLED/AMOLEDLCD, IPS
Screen size1.3 inches1.83 inches
Battery life1.25 days12 days
Released20232023

Every specification

117 specs
SpecSamsung Galaxy Watch6 - Wi-Fi · 40mmXiaomi Redmi Watch 3 Active
Design
width38.838.9
height40.446.9
volume14.11 cm³19.89 cm³
weight28.7 g42 g
thickness910.9
ATM rating5 ATM5 ATM
resolution432 x 432 px240 x 280 px
screen size1.3 inches1.83 inches
Display typeOLED/AMOLEDLCD, IPS
Has a displayYesYes
pixel density453 ppi202 ppi
width of band20 mm—
water resistanceWaterproofSweat resistant
Always-On DisplayYesNo
has a touch screenYesYes
waterproof depth rating50 m—
Watch band is replaceableYesYes
Has sapphire glass displayYesNo
Ingress Protection (IP) ratingIP68—
has branded damage-resistant glassNoNo
is designed for kids—No
Battery
charge time1.8 hours—
battery life1.25 days12 days
battery power300 mAh289 mAh
has wireless chargingYesNo
has a removable batteryNoNo
Has a solar power batteryNoNo
has a rechargeable batteryYesYes
battery life in power save mode100 hours—
Sensors
has GPSYesNo
has a compassYesNo
Has a barometerYesNo
has a gyroscopeYesNo
Has a cadence sensorNoNo
has an accelerometerYesYes
Monitors perspirationNoNo
Has a heart rate monitorYesYes
Has a temperature sensorYesNo
Monitors blood oxygenation levelsYesYes
Features
RAM2GB—
CPU speed2 x 1.4 GHz—
release date2023-07-262023-08-01
Has a stopwatchYesYes
Has smart alarmNoNo
Has call controlYesYes
Has silent alarmYesYes
has HRV trackingNo—
internal storage16GB—
measures VO2 maxYes—
Has notificationsYesYes
Has ECG technologyYesNo
Locates your phoneYesYes
has fall detectionYesNo
has voice commandsYesNo
Acquires GPS fasterNoNo
Has vibrating alertsYesYes
number of microphones11
shows readiness levelNo—
Can be used to answer callsYesYes
measures resting heart rateYesYes
has irregular heart rate warningsYesNo
has fast/slow heart rate notificationsYes—
Has a built-in camera remote control functionYesNo
has a front camera—No
Connectivity
has NFCYesNo
Wi-Fi versionWi-Fi 4 (802.11n)—
supports ANT+NoNo
supports Wi-FiYesNo
supports GalileoYes—
Bluetooth version5.35.3
has a cellular moduleNoNo
Is compatible with iOSNoYes
Is compatible with AndroidYesYes
Miscellaneous
Has passcodeYesNo
Has auto pauseYes—
Is compatible with WindowsNoNo
Is compatible with Mac OS XNoNo
has an external memory slotNoNo
Compatible with smart scalesYes—
has a battery level indicatorYesYes
has a socket for a 3.5 mm audio jackNoNo
Compatible with external heart rate monitorsYesYes
App & Software
Ad-freeYes—
Free appYesYes
Tracks BMIYes—
Has coachingYesYes
Includes mapsYes—
Supports routesYesYes
Has achievementsYesYes
Has goal settingYesYes
Has exercise diaryYesYes
Has weight trackingYesYes
Predicts start dateYesYes
Tracks water intakeYesYes
Has inactivity alertsYesYes
Has period notificationsYesYes
Has temperature trackingYesNo
Provides activity reportsYesYes
Counts how many calories you've burnedYesYes
Predicts ovulation—Yes
Can be personalised—Yes
Doesn’t require account—No
Displays fertile window notifications—Yes
Activity tracking
Measures paceYesNo
Tracks distanceYesNo
Tracks elevationYesNo
Designed for golfNoNo
Tracks your sleepYesYes
Tracks steps takenYesYes
Designed for divingNoNo
Has a route trackerYesYes
Has exercise taggingYesYes
Has multi-sport modeYesNo
Tracks calorie intakeYesYes
Provides sleep reportsYesYes
Detects activities automaticallyYesYes
Has a stroke counter for swimmingYesNo

Wrist Fit

Samsung Galaxy Watch6 Wi-Fi 40mm

Sits best on wrists ~43–58mm wide (≈ 11.5–15.5cm circumference).

Xiaomi Redmi Watch 3 Active

Sits best on wrists ~49–67mm wide (≈ 13.1–17.9cm circumference).

Frequently Asked Questions

Is the Samsung Galaxy Watch6 Wi-Fi 40mm bigger than the Xiaomi Redmi Watch 3 Active?

The Xiaomi Redmi Watch 3 Active is bigger — 38.9mm vs 38.8mm case width.

Which fits a smaller wrist better, the Samsung Galaxy Watch6 Wi-Fi 40mm or the Xiaomi Redmi Watch 3 Active?

The Samsung Galaxy Watch6 Wi-Fi 40mm suits wrists around 43–58mm wide, and the Xiaomi Redmi Watch 3 Active around 49–67mm. 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 Xiaomi Redmi Watch 3 Active 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.

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