Between the Watch SE (2nd gen) and Watch Ultra 3, the Watch SE (2nd gen) comes out ahead in weight, while the Watch Ultra 3 wins on battery life and peak brightness. Overall, the Watch SE (2nd gen) scores 56.1 and the Watch Ultra 3 scores 65.3 on our Mars Score.
Which should you buy?
The Watch Ultra 3 is the clear pick on raw spec strength, leading by 9.2 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the Watch SE (2nd gen) if you carry the device everywhere and weight or thickness has been the deciding factor before. The biggest gaps in its favor are weight.
Pick the Watch Ultra 3 if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. Its strongest claims are battery life, peak brightness, display size, among others.
Both ship with comparable cellular, so those specs don't separate the two — focus on the differences below.
Bottom line: the Watch Ultra 3 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Apple - Watch SE (2nd gen) wins
- ▲Weight — 29.00 g less. 33 vs 62.
Why Apple - Watch Ultra 3 wins
- ▲Battery life — 300.00% more. 72 h vs 18 h.
- ▲Peak brightness — 200.00% more. 3000 nits vs 1000 nits.
- ▲Display size — 14.61% more. 2.04 " vs 1.78 ".
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
- ▲Has ECG.
- ▲Has SpO2.
Spec comparison
Design
| Spec | Apple - Watch SE (2nd gen) | Apple - Watch Ultra 3 |
|---|---|---|
| Case size | 44 mm | 49 mmlead |
| Weight | 33 glead | 62 g |
| Case material | aluminum | titanium |
| Water resistanceⓘ | 5 ATM | 10 ATMlead |
Display
| Spec | Apple - Watch SE (2nd gen) | Apple - Watch Ultra 3 |
|---|---|---|
| Display size | 1.78 " | 2.04 "lead |
| Always-on display | false | truelead |
| Peak brightnessⓘ | 1000 nits | 3000 nitslead |
Health & Fitness
| Spec | Apple - Watch SE (2nd gen) | Apple - Watch Ultra 3 |
|---|---|---|
| ECG | false | truelead |
| SpO2 | false | truelead |
| Temperature sensor | false | truelead |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | Apple - Watch SE (2nd gen) | Apple - Watch Ultra 3 |
|---|---|---|
| Battery life | 18 h | 72 hlead |
| GPS | true | true |
| Cellular | true | true |
| NFC | true | true |
| OS | watchOS | watchOS |
Frequently asked
Which has longer battery life, Watch SE (2nd gen) or Watch Ultra 3?+
Watch Ultra 3 lasts 72h vs 18h.
Do Watch SE (2nd gen) or Watch Ultra 3 support ECG?+
Watch Ultra 3 supports ECG; Watch SE (2nd gen) does not.
Which has cellular, Watch SE (2nd gen) or Watch Ultra 3?+
Both offer cellular variants.
Spec-level deep dives
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