This comparison puts the Apple Watch SE 3 and OnePlus Watch 4 side by side — two smartwatches measured against the same 32-spec sheet, with every meaningful gap scored and explained. On our weighted VS Score the OnePlus Watch 4 finishes ahead, 85 to 64 — a decisive result.
The single biggest measurable gap is battery life: 18 h vs 120 h. None of our retail partners currently lists the OnePlus Watch 4, so availability may be limited and price cannot factor into this comparison.
Tap a category to see which one wins it.
Design
Apple Watch SE 388
OnePlus Watch 467
Apple Watch SE 3 wins Design
Display
Apple Watch SE 333
OnePlus Watch 467
OnePlus Watch 4 wins Display
Health & fitness
Apple Watch SE 371
OnePlus Watch 4100
OnePlus Watch 4 wins Health & fitness
Battery
Apple Watch SE 324
OnePlus Watch 4100
OnePlus Watch 4 wins Battery
Connectivity
Apple Watch SE 382
OnePlus Watch 480
Apple Watch SE 3 wins Connectivity
Software
Apple Watch SE 3100
OnePlus Watch 40
Apple Watch SE 3 wins Software
64Points
85Points
Where the Apple Watch SE 3 beats the OnePlus Watch 4
16.6 g less weight ?26.4 g vs 43 g
0.28 " more display size ?1.78 " vs 1.5 "
30 min less charging time ?45 min vs 75 min
0.1 more Bluetooth version ?5.3 vs 5.2
32 GB more onboard storage ?64 GB vs 32 GB
Where the OnePlus Watch 4 beats the Apple Watch SE 3
3.4 mm more case size ?47.4 mm vs 44 mm
18 px more resolution ?466 px vs 448 px
2,000 nits more peak brightness ?3,000 nits vs 1,000 nits
The spec sheet pulls in both directions. These are the gaps big enough to shape the decision — with the actual figures, and what each one means in real-world use.
Battery lifeBattery
18 h vs 120 h — 6.7× more for the OnePlus Watch 4
Estimated hours of use between charges.
Blood oxygen (SpO2)Health & fitness
No vs Yes — only the OnePlus Watch 4 has it
Measures blood-oxygen saturation.
ECGHealth & fitness
No vs Yes — only the OnePlus Watch 4 has it
Takes an electrocardiogram to check heart rhythm.
Peak brightnessDisplay
1,000 nits vs 3,000 nits — 3× more for the OnePlus Watch 4
A brighter screen is easier to read in sunlight.
Dual-frequency GPSConnectivity
No vs Yes — only the OnePlus Watch 4 has it
L1+L5 GPS gives more accurate tracking in cities and forests.
Which one should you buy?
There is no single answer — it depends on what you will actually use it for. Match your priority to the pick below.
Best for health & fitnessOnePlus Watch 4 takes the category 100 to 71 — driven by blood oxygen (SpO2) (No vs Yes).
Best for designApple Watch SE 3 takes the category 88 to 67 — driven by weight (26.4 g vs 43 g).
Best for batteryOnePlus Watch 4 takes the category 100 to 24 — driven by battery life (18 h vs 120 h).
Best for displayOnePlus Watch 4 takes the category 67 to 33 — driven by peak brightness (1,000 nits vs 3,000 nits).
Best for softwareApple Watch SE 3 takes the category 100 to 0 — driven by onboard storage (64 GB vs 32 GB).
The safe all-rounderOnePlus Watch 4 wins more of the categories that carry real weight, topping the overall VS Score at 85.
Where each one falls short
Apple Watch SE 3
Battery life: 18 h vs 120 h
Blood oxygen (SpO2): No vs Yes
ECG: No vs Yes
1 spec is unreported (shown as Unknown) and excluded from its scores.
OnePlus Watch 4
Weight: 26.4 g vs 43 g
Onboard storage: 64 GB vs 32 GB
Display size: 1.78 " vs 1.5 "
3 specs are unreported (shown as Unknown) and excluded from its scores.
What matters to you?
Drag the sliders to weight each category and re-rank the products to suit your priorities.
Design
Display
Health & fitness
Battery
Connectivity
Software
Your ranking
Apple Watch SE 3Your pick66
OnePlus Watch 4Your pick80
Score breakdown
Design
Apple Watch SE 388
OnePlus Watch 467
Decided by weight (26.4 g vs 43 g) and case size (44 mm vs 47.4 mm).
Display
Apple Watch SE 333
OnePlus Watch 467
Decided by peak brightness (1,000 nits vs 3,000 nits) and display size (1.78 " vs 1.5 ").
Health & fitness
Apple Watch SE 371
OnePlus Watch 4100
Decided by blood oxygen (SpO2) (No vs Yes) and ECG (No vs Yes).
Battery
Apple Watch SE 324
OnePlus Watch 4100
Decided by battery life (18 h vs 120 h).
Connectivity
Apple Watch SE 382
OnePlus Watch 480
Decided by dual-frequency GPS (No vs Yes) and Bluetooth version (5.3 vs 5.2).
Software
Apple Watch SE 3100
OnePlus Watch 40
Decided by onboard storage (64 GB vs 32 GB).
How the VS Score works — and what it can’t tell you
Every measurable spec is scored relative to this matchup: the best value here earns 100%, the worst 0%, and everything between scales linearly. Each spec then counts according to an editorial weight that reflects real-world impact — a battery-capacity gap moves the score far more than a colour-options list. The category scores above are the weighted results inside each group, and the overall VS Score rolls all of them together; the evidence line under each category names the specs that actually decided it.
Unknown values are never estimated. A spec a product doesn’t report simply drops out of that product’s scoring — it isn’t penalised with a guess — and a spec only one side reports can never produce a “win”. The trade-off is honest but real: a thinner spec sheet means a score built on fewer data points, which is why the completeness figures are disclosed under About this data.
Most importantly: a spec-sheet lead is not the same as a better product. Megapixels, gigahertz and benchmark points describe capacity, not experience — image processing, software optimisation, thermals, haptics and ergonomics decide how a device actually feels, and no table captures reliability or long-term support quality. Treat the scores as a structured summary of what can be measured, read the caveats under each key difference, and use the weight tuner to re-rank the comparison by what matters to you.
Design
Weight ?
26.4 g
43 g
A lighter watch is more comfortable to wear all day.
Case size ?
44 mm
47.4 mm
The case diameter; larger cases fit bigger displays, smaller ones suit slimmer wrists.
Case material ?
Glass front
Glass front (Sapphire crystal)
The case material (e.g. aluminium, titanium).
Water resistance ?
5 ATM
5 ATM
A higher ATM rating allows swimming and diving.
Always-on display ?
✓Apple Watch SE 3
? Unknown (OnePlus Watch 4)
Shows the time and stats without raising your wrist.
Sapphire glass ?
✓Apple Watch SE 3
✓OnePlus Watch 4
A scratch-resistant sapphire crystal protects the screen.
Colors ?
Midnight, Starlight
Midnight Titanium, Evergreen Titanium
The case and band colour options the watch is sold in.
Display
Display size ?
1.78 "
1.5 "
A larger display is easier to read and interact with.
Resolution ?
448 px
466 px
A higher pixel count produces sharper text and graphics.
Display type ?
Retina LTPO OLED
LTPO AMOLED
The screen technology (e.g. AMOLED).
Peak brightness ?
1,000 nits
3,000 nits
A brighter screen is easier to read in sunlight.
Health & fitness
Heart rate monitor ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Continuously tracks your heart rate.
Blood oxygen (SpO2) ?
✗Apple Watch SE 3
✓OnePlus Watch 4
Measures blood-oxygen saturation.
ECG ?
✗Apple Watch SE 3
✓OnePlus Watch 4
Takes an electrocardiogram to check heart rhythm.
Blood pressure ?
✗Apple Watch SE 3
✗OnePlus Watch 4
Estimates blood pressure from the wrist.
Sleep tracking ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Monitors sleep stages and quality.
Built-in GPS ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Tracks routes and distance without a phone.
Skin temperature ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Senses skin temperature for health insights.
Fall detection ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Detects hard falls and can call for help.
Sport modes ?
? Unknown (Apple Watch SE 3)
100
More tracked workout types suit more activities.
Battery
Battery life ?
18 h
120 h
Estimated hours of use between charges.
Fast charging ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Tops up quickly from empty.
Wireless charging ?
✓Apple Watch SE 3
? Unknown (OnePlus Watch 4)
Charges on a wireless pad or puck.
Charging time ?
45 min
75 min
How long a full charge takes; lower is better.
Connectivity
Bluetooth version ?
5.3
5.2
A newer Bluetooth version improves range and efficiency.
Wi-Fi ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Connects to Wi-Fi for updates and sync without a phone.
Dual-frequency GPS ?
✗Apple Watch SE 3
✓OnePlus Watch 4
L1+L5 GPS gives more accurate tracking in cities and forests.
LTE / cellular ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Make calls and stream without your phone nearby.
NFC payments ?
✓Apple Watch SE 3
✓OnePlus Watch 4
Pay contactlessly from your wrist.
Speaker & microphone ?
✓Apple Watch SE 3
? Unknown (OnePlus Watch 4)
Take calls and use a voice assistant on the watch.
Software
Operating system ?
watchOS 26
OxygenOS Watch 8 + Wear OS 6.0
The watch software platform.
Onboard storage ?
64 GB
32 GB
More storage holds more offline music and apps.
About this data
Specifications are compiled from each manufacturer’s official spec sheet, cross-checked against trusted specification databases, and normalised into one schema so identical things are compared identically.
Specifications last verified July 8, 2026.
Data completeness: Apple Watch SE 3 97% and OnePlus Watch 4 91% of the 32 specs in this category. Anything we could not verify is shown as Unknown — never estimated — and is excluded from all scores.
Prices and availability come from live retailer feeds via our shopping partners and refresh throughout the day; a missing price means no partner currently lists the product, not that it is discontinued.
Want the full picture? Our editorial guidelines explain how we research products, weight the scores and stay independent.
Spotted an error in a spec? Tell us and we will correct the sheet.
The OnePlus Watch 4 is the clear winner, scoring 85 to 64 on our VS Score. It leads on Display, Health & fitness and Battery. The Apple Watch SE 3 answers back with stronger Design, Connectivity and Software. Pick the OnePlus Watch 4 unless Design and Connectivity matters most to you — then the Apple Watch SE 3 is the smarter buy.