iPhoneiOS · phone · 2026

iPhone Duo — unfolded viewport size

951 × 669CSS px · 3× DPR · 2670×1878 physical

The iPhone Duo — unfolded gives web pages a 951 × 669 CSS pixel viewport in its natural landscape orientation. That’s the width your layout and media queries actually see, not the 2670 × 1878 physical pixels of the screen: with a device pixel ratio of 3, every CSS pixel is 3 × 3 real pixels.

CSS viewport951 × 669what web pages get
Portrait (turned)669 × 951if you turn it upright
Device pixel ratio3×1 CSS px = 3 × 3 screen pixels
Physical resolution2670 × 18787.6″ screen
Visible in the browser951 × 589Safari (iPhone Duo, unfolded), first load
Released2026iOS phone

See your site on an iPhone Duo — unfolded

Paste your address (or localhost:3000). doesitfit shows it at exactly 951 × 669, with Safari (iPhone Duo, unfolded)’s bars if you want them, and tells you if anything spills.

Free, no sign-up. Or ask Claude, ChatGPT or Codex to check it.

What a web page actually sees

The full viewport is 951 × 669, but the browser’s own bars take some of it. In Safari (iPhone Duo, unfolded) a page gets about 951 × 589 on first load (an iPad-style toolbar across the top). That’s your real “above the fold”. Use 100dvh instead of 100vh for full-height sections, or they’ll hide behind the toolbar (why).

SettingWidthHeight
Full viewport951px669px
Visible on first load (Safari (iPhone Duo, unfolded))951px589px
Portrait (turned) (full)669px951px

What it means for your CSS

Breakpoints

At 951px: Tailwind uses md (sm: md: styles apply); Bootstrap uses md. Turned upright (669px): Tailwind uses sm (sm: styles apply), Bootstrap sm.

Tailwind breakpoints on real devices

Content width

With 16px of padding on each side your text column is 919px; with 24px it’s 903px. Text closer than 8px to the edge looks cramped (more).

Sharp images

A full-width image needs about 2853px of real pixels (951 × 3).

<img src="hero-2853.jpg"
  srcset="hero-800.jpg 800w, hero-2853.jpg 2853w"
  sizes="100vw" alt="…">

Styles for this width

Content-first breakpoints beat device lists, but if something breaks at this width:

@media (max-width: 951px) {
  /* screens 951px wide and narrower */
}

How common is 951 × 669?

951 × 669 isn’t in StatCounter’s top lists for Aug 2026 on its own, but nearby sizes behave the same way. See the most common screen sizes.

Compare:

Everything about the 951 × 669 viewport · All iPhone sizes

Questions people ask

What is the viewport size of the iPhone Duo — unfolded?

951 × 669 CSS pixels in its natural landscape orientation (669 × 951 turned upright), with a device pixel ratio of 3. The screen itself is 2670 × 1878 physical pixels.

How much of the iPhone Duo — unfolded screen does a web page get in Safari?

About 951 × 589 on first load: the an iPad-style toolbar across the top. Design your first screen for that height, not the full 669px.

Which CSS breakpoint does the iPhone Duo — unfolded fall into?

At 951px wide, Tailwind CSS uses md (sm: md: styles apply) and Bootstrap uses its md tier. Turned upright (669px) Tailwind uses sm (sm: styles apply).

How wide should images be for the iPhone Duo — unfolded?

A full-width image needs about 2853px of real pixels (951 CSS px × DPR 3) to look sharp. Use srcset so smaller screens don’t download it.

How can I test my website on an iPhone Duo — unfolded without one?

Open doesitfit.lol, paste your address (localhost works too) and pick the iPhone Duo — unfolded. It shows your site at exactly 951 × 669 CSS pixels and flags anything that spills past the edge.

Guides that help

About these numbers

Confidence: Good: from official specs and reports. Opens sideways like a book: 951 × 669 landscape, camera under the screen. iPhone Duo: the outer screen is 466 × 678, but iOS 27 reserves an 84 pt strip on its right edge for the camera, clock and Safari’s buttons, so web pages lay out at 382 px wide. The inner screen is 951 × 669 in its natural landscape orientation (the 890 × 626 figure quoted on some sites is wrong). Sizes come from Apple’s screenshot specs and the iOS 27.1 simulator; Safari’s exact heights on the Duo have not been read with JavaScript yet.

Sources include DeviceAtlas, Chrome DevTools device list (EmulatedDevices.ts), iosref.com, ios-resolution.com. Researched September 2026.