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MobileIQ

Head to head

Apple Apple Watch Series 6 40mmvsApple Apple Watch Series 6 44mm

Released
2020-09-18endoflife.date, retrieved 2026-09-13
Security updates until
Not published by the makerApple UK — watchOS 27 compatible models, retrieved 2026-09-22
Released
2020-09-18endoflife.date, retrieved 2026-09-13
Security updates until
Not published by the makerApple UK — watchOS 27 compatible models, retrieved 2026-09-22

0 wins for Apple Watch Series 6 40mm0 wins for Apple Watch Series 6 44mm1 gap borderline0 differences you won’t notice

Verdict: nothing you’d notice between them

On the makers’ published figures, neither the Apple Watch Series 6 40mm nor the Apple Watch Series 6 44mm wins a row by a gap you would notice. One gap is borderline, a difference most people would not notice: weight (case only) (30.5 g against 36.5 g) for the Apple Watch Series 6 40mm. Both state the same peak brightness and battery life (maker's claim). The other 24 rows have no threshold or no direction to judge by, so nobody wins them.

True to scale

Apple Watch Series 6 40mm · 40 × 34 mmApple Watch Series 6 44mm · 44 × 38 mm

Case outlines from each maker’s published dimensions, drawn to scale. Corner rounding is our drawing convention, not a measurement.

Specifications

A win is marked only where the figures can be ranked and the gap is one you could notice on the wrist. A row the site has no threshold for says whether the two differ, and that it is not ranking them. = marks the same figure on both, ≠ not ranked a difference with no ranking. Every figure carries its source.

Body

SpecificationApple Watch Series 6 40mmApple Watch Series 6 44mm
DimensionsDiffers, but not ranked.
40 x 34 x 10.7 mmOfficial
44 x 38 x 10.7 mmOfficial
Case size
Case shapeSame.
rectangularOfficial
rectangularOfficial
Weight (case only)

Marginal — most people won’t notice.

Case materialSame.
AluminiumOfficial
AluminiumOfficial
Water ratingSame.
Water resistant 50 metres under ISO standard 22810:2010Official
Water resistant 50 metres under ISO standard 22810:2010Official

Display

SpecificationApple Watch Series 6 40mmApple Watch Series 6 44mm
Display typeSame.
Always-On Retina LTPO OLED displayOfficial
Always-On Retina LTPO OLED displayOfficial
Display areaDiffers, but not ranked.
759mm²Official
977mm²Official
ResolutionDiffers, but not ranked.
324 x 394Official
368 x 448Official
Peak brightnessSame.
1000nitsOfficial
1000nitsOfficial
Always-on displaySame.

Platform

SpecificationApple Watch Series 6 40mmApple Watch Series 6 44mm
Operating systemSame.
watchOSOfficial
watchOSOfficial
ChipSame.
S6 SiPOfficial
S6 SiPOfficial
StorageSame.

Battery

SpecificationApple Watch Series 6 40mmApple Watch Series 6 44mm
Battery life (maker's claim)Same.
ChargingSame.
Magnetic charging cableOfficial
Magnetic charging cableOfficial

Health

SpecificationApple Watch Series 6 40mmApple Watch Series 6 44mm
SensorsSame.
Blood oxygen sensor, electrical heart sensor, third-generation optical heart sensor, compass, always-on altimeter, accelerometer, gyroscope, ambient light sensorOfficial
Blood oxygen sensor, electrical heart sensor, third-generation optical heart sensor, compass, always-on altimeter, accelerometer, gyroscope, ambient light sensorOfficial
ECGSame.
Blood oxygenSame.
GPSSame.
GPS/GNSSOfficial
GPS/GNSSOfficial

Connectivity

SpecificationApple Watch Series 6 40mmApple Watch Series 6 44mm
Cellular modelSame.
UK networks with eSIMSame.
EE, Vodafone, Three3rd party
EE, Vodafone, Three3rd party
Wi-FiSame.
802.11b/g/n 2.4GHz and 5GHzOfficial
802.11b/g/n 2.4GHz and 5GHzOfficial
BluetoothSame.
NFC paymentsSame.

Compatibility

SpecificationApple Watch Series 6 40mmApple Watch Series 6 44mm
Works withSame.
iPhone 6s or later with iOS 14 or laterOfficial
iPhone 6s or later with iOS 14 or laterOfficial
CompatibilitySame.
iPhone onlyOfficial
iPhone onlyOfficial
8 attributes neither watch has a sourced figure for

Strap width · Display size · RAM · Battery capacity · Charge to 80% · Skin temperature · Blood pressure · Cellular model price. Rows appear as sources are cited — a gap in our data, not a statement about either watch.