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Watch Series 9 vs Redmi Watch 4

Apple Watch Series 9 vs Xiaomi Redmi Watch 4

What Watch Series 9 does better (5) and where Redmi Watch 4 wins (4) — every spec side by side.

Apple · 2023Watch Series 9

5.9Score

5 advantages≈ $680

Xiaomi · 2023Redmi Watch 4

7.0Score

4 advantages≈ $75

Higher score

8.2Display5.0

8.6Health tracking5.0

7.9Smart features6.5

6.0Build & durability8.2

Dimensions

Size comparison

Watch Series 9Redmi Watch 4

	Watch Series 9	Redmi Watch 4	Difference
Height	45 mm	47.6 mm	−2.6 mm
Width	38 mm	41.1 mm	−3.1 mm
Thickness	10.7 mm	10.5 mm	+0.2 mm
Weight	42 g	32 g	+11 g

Drawn to the same scale from the official dimensions (front and side).

Why is Watch Series 9 better than Redmi Watch 4?

Peak brightness2,000 nits vs 600 nits3.3×
LTE (cellular)Yes · Redmi Watch 4: No
Storage64 GB vs 16 GB4×
eSIMYes · Redmi Watch 4: No
Pixel density326 ppi vs 302 ppi+8%

Why is Redmi Watch 4 better than Watch Series 9?

Battery life (smartwatch mode)0.8 days vs 20 days25×
Weight42.3 g vs 31.5 g+34%
Screen size1.9″ vs 1.97″+4%
Battery capacity308 mAh vs 470 mAh+53%

Specifications

Side by side

Only differences	Apple Watch Series 9≈ $6805.9	Xiaomi Redmi Watch 4≈ $757.0
Design & durability
Case size	45 mm	48 mm
Weight	42.3 g	31.5 g
Thickness	10.7 mm	10.5 mm
Height	45 mm	47.6 mm
Width	38 mm	41.1 mm
Case material	Stainless steel	Aluminium
Sapphire crystal	Yes	—
Lens / cover glass	Sapphire crystal glass	—
Strap material	—	TPU
Water resistance	5 ATM	5 ATM
Ingress protection	IP6X	—
Water rating (maker)	50 m / 5 ATM	50 m / 5 bar / 5 ATM
Colours	Graphite, Silver, Gold, Red	Black, White
Display
Screen size	1.9″	1.97″
Display technology	OLED	AMOLED
Panel	Retina LTPO OLED	AMOLED
AMOLED / OLED display	Yes	Yes
Always-on display	Yes	—
Touchscreen	—	Yes
Resolution (width)	396 px	390 px
Resolution (height)	484 px	450 px
Pixel density	326 ppi	302 ppi
Peak brightness	2,000 nits	600 nits
LTPO display	Yes	—
Refresh rate	60 Hz	60 Hz
Battery
Battery life (smartwatch mode)	0.8 days	20 days
Battery life (hours)	18 h	—
Battery capacity	308 mAh	470 mAh
Battery type	Li-Ion	Li-Po
Wireless charging	Yes	—
Charged in 30 min	53%	—
Health sensors
Optical heart rate	Yes	Yes
Blood oxygen (SpO2)	Yes	Yes
ECG	Yes	—
Skin temperature	Yes	—
Temperature sensor	Yes	—
Sleep tracking	Yes	Yes
Sensors	Accelerometer, gyro, heart rate, barometer, always-on altimeter, compass, SpO2, VO2max, temperature (body)	Accelerometer, heart rate, compass, gyro, SpO2
Sports & navigation
Built-in GPS	Yes	Yes
Satellite systems	GLONASS, GALILEO, BDS, QZSS	GLONASS, GALILEO, BDS, QZSS
Barometric altimeter	Yes	—
Compass	Yes	Yes
Multisport / triathlon mode	Yes	—
Connectivity
NFC payments	Yes	Yes
LTE (cellular)	Yes	No
eSIM	Yes	No
Wi-Fi	Wi-Fi 4	—
Bluetooth	5.3	5.3
Ultra Wideband	Yes	—
Smart features
Calls from the wrist	Yes	—
Speaker	Yes	Yes
Microphone	Yes	—
Voice assistant	Yes	—
Music on the watch	Yes	—
Storage	64 GB	16 GB
Platform
Operating system	watchOS 10	HyperOS
Platform	watchOS	Proprietary
Works with	iOS	iOS, Android
Chipset	Apple S9	—