Apple rates the Apple Watch Ultra 4 display at up to 3000 nits at its brightest and 1 nit at its dimmest, on a 422 x 514 pixel always-on panel that can drop its refresh rate to 1 Hz. The glass in front of it is flat sapphire, the case is 49 mm titanium, and the watch is in stores on Friday, September 18 from $799.
The brightness ceiling is the number that matters in open sun, and it is three times the 1000 nit rating of the Apple Watch SE 3 and half again the 2000 nits of the new Series 12, by our arithmetic on Apple’s figures. It is also identical to the Ultra 3 rating from last September, and so is every other line in Apple’s display specification.
Key facts: the Ultra 4 display specification
| Item | What Apple publishes |
|---|---|
| Type | Always-On Retina display, wide-angle OLED, LTPO3 |
| Resolution | 422 x 514 pixels |
| Area | 1245 square millimetres |
| Pixel density | 326 ppi |
| Peak brightness | 3000 nits |
| Minimum brightness | 1 nit |
| Refresh rate | Down to 1 Hz |
| Front crystal | Flat sapphire |
| Case | 49 mm Grade 5 titanium, natural or black |
3000 nits is a ceiling, not a setting
Apple publishes 3000 nits as a peak. It does not say how long the display holds that level, at what ambient light it reaches it, or whether any watch face or mode is capped below it.
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That matters more on a watch than on a phone, because the screen is the only readout you have mid-event and you cannot shade it with your other hand while running. What Apple does state is the range: 3000 nits down to 1 nit on the same panel.
The 1 nit floor, and the dark
The 1 nit minimum is the same floor Apple gives the Series 12, and it is the figure that describes a glance at a watch face at 3 a.m. in a tent. Apple has published no detail about how the watch selects that level, and no numbers for any night-time display mode.
It is worth being precise here: 1 nit is a brightness floor, not a claim about colour, and Apple makes no statement about how the display behaves under a head torch or after dark adaptation.
LTPO3 at 1 Hz, and the battery figure that is not attached to it
LTPO3 is the panel technology that lets the refresh rate fall as low as 1 Hz, which is how an always-on display keeps showing the time without redrawing 60 times a second. Apple lists the capability and stops there.
There is no published power figure for the display, and none of the battery ratings is broken down by screen state. Apple’s headline numbers are up to 50 hours of normal use, up to 84 hours in Low Power Mode, up to 25 hours in Extended Workout mode and up to 45 hours in the new Max Extended Workout mode with one-second GPS, and all of them are stated without a display condition. The Ultra 4 announcement has the full set.
Area in square millimetres, and the diagonal Apple never gives
Apple measures Apple Watch screens by area rather than by diagonal, so there is no inch figure for any of them. The Ultra 4 panel covers 1245 square millimetres, against 1196 for the 46 mm Apple Watch Series 12 and 970 for the 42 mm model.
| Display | Ultra 4 | Ultra 3 | Series 12, 46 mm |
|---|---|---|---|
| Resolution | 422 x 514 | 422 x 514 | 416 x 496 |
| Area | 1245 sq mm | Not published in this form | 1196 sq mm |
| Pixel density | 326 ppi | 326 ppi | 326 ppi |
| Peak brightness | 3000 nits | 3000 nits | 2000 nits |
| Minimum brightness | 1 nit | 1 nit | 1 nit |
| Front crystal | Flat sapphire | Flat sapphire | Ceramic Shield 2 on aluminium, sapphire on titanium and ceramic |
Our arithmetic on those areas, not Apple’s: the Ultra 4 shows about 4 percent more screen than the largest Series 12 and about 28 percent more than the smallest one.
What Apple has not said
- No sustained brightness figure, and no condition under which 3000 nits is reached.
- No display power draw, and no battery rating split by screen state.
- No scratch or impact claim for the sapphire crystal.
- No diagonal measurement in inches for any Apple Watch.
- No statement on refresh behaviour during a workout or in Low Power Mode.
Ultra 4 orders opened on September 9 and the watch reaches stores on Friday, September 18. watchOS 27 lands first, on Monday, September 14, as a free update for Ultra 2 and later, the same day as iOS 27, and our live blog from the event has the announcements as they happened.
