iPhone Duo Aspect Ratio & Screen Resolutions
The iPhone Duo has two displays: a 7.6-inch inner screen that opens into a wide, almost-square panel, and a 5.4-inch outer screen that behaves like a tall phone. The resolutions below are Apple's published figures, and the ratios are what those figures reduce to.
Screen specifications
| Display | Size | Resolution | PPI | Aspect ratio |
|---|---|---|---|---|
| Inner display | 7.6" | 1878 × 2670 | 430 | 2670:1878 — reduces to 445:313 (≈ 1.42:1) |
| Outer display | 5.4" | 1398 × 2034 | 460 | 2034:1398 — reduces to 339:233 (≈ 1.45:1) |
Inner display
1878 × 2670 pixels at 430 ppi. Apple publishes this panel as 1878 × 2670 pixels at 430 ppi. The longer edge divided by the shorter edge is 2670 ÷ 1878 = 1.4217, and 2670:1878 reduces exactly to 445:313. It is therefore close to a 10:7 frame in landscape — but not exactly 10:7, because 2670:1878 does not divide evenly. A hard-coded 10:7 value misses by about 0.5%: small enough to be invisible in a layout, large enough that a pixel-exact crop or a wallpaper built for 10:7 will not land flush.
Outer display
1398 × 2034 pixels at 460 ppi. Apple publishes this panel as 1398 × 2034 pixels at 460 ppi. Longer over shorter is 2034 ÷ 1398 = 1.4549, and 1398:2034 reduces exactly to 233:339. Apple describes the two panels as sharing an aspect ratio, and they are close — but the outer panel is about 2.3% taller than the inner one rather than an exact match, which matters only if you intend to hard-code a single number for both screens.
iPhone Duo wallpaper size
A wallpaper is prepared per panel, because the two screens have different ratios. Use the native resolution of whichever screen the wallpaper is for — 1878 × 2670 for the inner display and 1398 × 2034 for the outer display — so the image is neither cropped nor stretched.
If you need to adapt a single image to both, use the image crop calculator to reach each ratio, and the image resize calculator to hit the exact pixel size without distortion.
iPhone Duo Aspect Ratio & Screen Resolutions FAQ
What is the iPhone Duo inner display aspect ratio?
The 1878 × 2670 inner panel reduces exactly to 313:445, and its longer edge over its shorter edge is about 1.42:1. That puts it close to a 10:7 landscape frame, but not exactly there — the published resolution does not divide evenly.
What is the outer display ratio?
The 1398 × 2034 outer panel reduces to 233:339, and its longer-over-shorter value is about 1.45:1 — a little taller proportionally than the inner panel.
What size should an iPhone Duo wallpaper be?
Prepare one size per screen. For the inner display use 1878 × 2670; for the outer display use 1398 × 2034. Using the exact native resolution avoids both cropping and upscaling.
Do the two screens share an aspect ratio?
Apple says they are matched, and in practice they are close — but the published resolutions work out about 2.3% apart. A layout tuned for one will be slightly off on the other unless the system handles the scaling, which Apple's APIs do.
Source: Apple technical specifications (iPhone Duo), September 2026.