iPhone Duo screen size: inner and outer display resolution explained
7.6 inches inside, 5.4 inches outside: resolution, pixel density, brightness and what the numbers mean for reading, video and apps.
iPhone Duo has two displays, and they are not just big and small versions of the same thing. Here are the numbers from Apple's spec sheet and what they mean in use.
The inner display
- 7.6 inches diagonally (7.58 inches measured as a standard rectangle).
- 1878 x 2670 pixels at 430 ppi.
- Folding OLED with a custom nano-texture finish to reduce glare, made of more than 10 ultrathin layers.
- Under-display FaceTime camera, hidden until you need it.
Apple says it is 50 percent larger than the iPhone 18 Pro Max display. It is the screen for reading, video, Split View and editing. Wondering about the fold line? Read our crease and nano-texture explainer.
The outer display
- 5.4 inches diagonally (5.36 inches as a rectangle).
- 1398 x 2034 pixels at 460 ppi, slightly sharper than the inner screen.
- Apple says it has more than 90 percent of the screen area of iPhone 18 Pro.
This is the everyday phone screen: messages, quick replies, maps and calls. Apple also notes the aspect ratio is consistent across the inner and outer displays, which helps apps move between them cleanly.
What both screens share
ProMotion up to 120Hz, Always-On, Dynamic Island, HDR, True Tone, P3 wide color, a 2,000,000:1 contrast ratio, 1000 nits typical brightness, 1600 nits HDR peak, 3000 nits outdoor peak and a 1 nit minimum. Both also support Apple Pencil (USB-C).
Which screen uses more battery?
The outer one is far more efficient: up to 44 hours of video playback on the outer display versus 31 hours on the inner display. Details in our battery life guide.
Protecting the inner screen
Folding screens need different care. See our inner screen care guide before you add any protector.
Recording on iPhone Duo? Try PromptSlate Studio
A 7.6-inch screen is a great teleprompter. PromptSlate Studio puts your script on the big display while the camera rolls, with the text sized for reading at arm's length. See PromptSlate Studio for iPhone Duo.
Related iPhone Duo guides
From the maker
Get PromptSlate Studio on the App Store
Write, prompt and record in one focused workspace. Out now — $9.99 one-time, no subscription. Every download supports independent development of new apps.
See PromptSlate Studio details · Also in the works: DuoSketch
Spotted something to fix, or an app we should cover?
This article is independent research, cross-checked against Apple's developer documentation. If something's out of date, or you know an app that deserves a look, let us know — and if you're building for iPhone Duo yourself, we're happy to talk.
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