How large is uncropped video on each screen?
A diagonal screen number does not tell you the size of a video when the screen and video use different aspect ratios. The estimates below divide Apple’s published resolution by its published pixels per inch, then fit the largest centered rectangle for each video format without cropping.
| Uncropped format | Duo inner display | Duo outer display | iPhone 18 Pro Max |
|---|---|---|---|
| 16:9 video | About 7.12-inch effective diagonal / 21.7 sq in | About 5.07-inch / 11.0 sq in | About 5.85-inch / 14.6 sq in |
| 4:3 video | About 7.28-inch / 25.4 sq in | About 5.07-inch / 12.3 sq in | About 4.78-inch / 11.0 sq in |
| 1.85:1 movie | About 7.06-inch / 20.8 sq in | About 5.03-inch / 10.6 sq in | About 6.03-inch / 15.2 sq in |
| 2.39:1 movie | About 6.73-inch / 16.1 sq in | About 4.79-inch / 8.2 sq in | About 6.76-inch / 16.3 sq in |
Compare the decision, not only the headline
| Decision factor | iPhone Duo | iPhone 18 Pro Max |
|---|---|---|
| Primary display idea | 7.6-inch inner display plus 5.4-inch outer display. | 6.9-inch conventional display. |
| Best reason to choose | Two-app layouts, larger inner workspace, and different physical positions. | A familiar slab-phone workflow and Pro Max-specific preferences. |
| Physical tradeoff | 254 g and 11.3 mm listed closed depth. | 249 g and 8.75 mm listed depth. |
| Camera reach | 0.5x, 1x, and 2x optical-quality options; no dedicated telephoto camera listed. | Dedicated Fusion Telephoto plus up to 8x optical-quality zoom. |
| Battery reference | Up to 31 h inner / 44 h outer video playback. | Up to 45 h video playback. |
Who should choose the Duo form factor
- You can name a repeated task that benefits from side-by-side apps or a larger inner canvas.
- You accept a foldable mechanism and are comfortable following more conservative care habits.
- Your carrier supports the eSIM workflow you need.
- You value a new interaction model more than a simple spec-sheet win.
Who should wait for more evidence
If your decision depends on long-term hinge durability, repair pricing, a specific banking app, or a carrier’s exact activation flow, wait for authoritative documentation or corroborated independent testing. Those are not answered by a launch page alone.
For the official numbers, use the specs reference. For launch timing, see availability and release dates.
Confirmed
- Apple lists the Duo inner display as 1878 by 2670 pixels at 430 ppi and the outer display as 1398 by 2034 pixels at 460 ppi.
- Apple lists the iPhone 18 Pro Max display as 2868 by 1320 pixels at 460 ppi.
- The uncropped video figures are reproducible geometry estimates calculated from those official specifications.
Provisional
- The estimates do not represent a hands-on playback test. Final app layouts, cutouts, rounded corners, the fold area, controls, and zoom-to-fill behavior can change the visible picture.
FAQ
Is 16:9 video bigger on iPhone Duo than iPhone 18 Pro Max?
Yes on the open inner display, based on Apple’s official resolution and pixel-density figures. The idealized uncropped 16:9 rectangle is about 21.7 square inches on the Duo inner display versus 14.6 square inches on iPhone 18 Pro Max, or roughly 49% larger by area. Actual viewable video may be smaller.
Why does iPhone Duo show black bars around video?
The Duo inner display is closer to 1.42:1, while common video is 16:9, 1.85:1, or 2.39:1. An uncropped player preserves the entire frame and uses bars for the remaining screen area. Zoom-to-fill removes some bars by cropping the picture.
Are ultrawide movies bigger on iPhone Duo?
Not necessarily. For uncropped 2.39:1 video, the resolution-based estimates are nearly identical: about a 6.73-inch effective diagonal on the Duo inner display and 6.76 inches on iPhone 18 Pro Max. App behavior and cutouts can still change the real result.
Which one is easier to carry?
Use current official dimensions and weights plus the case you plan to use. The Duo’s open and closed measurements describe a different handling problem, not a simple “bigger or smaller” answer.
Sources
- Apple iPhone DuoOfficial comparison and feature context.
- Apple iPhone Duo specificationsOfficial Duo display resolution, pixel density, dimensions, weight, and battery claims.
- Apple iPhone 18 Pro specificationsOfficial Pro Max display resolution, pixel density, dimensions, weight, camera, and battery claims.
- Reddit: usable video area comparisonFresh demand signal for 16:9, 4:3, open, and closed playback comparisons.
- Reddit: iPhone Duo aspect ratio discussionIndependent demand signal for 16:9 and movie-format questions.