440 × 956 viewport: which devices use it?
440 × 956CSS px · 19.6:9
440 × 956 is the CSS viewport of 3 devices in our research, including the iPhone 18 Pro Max, iPhone 17 Pro Max, iPhone 16 Pro Max. Turned sideways it becomes 956 × 440.
| Device | CSS viewport | DPR | Physical pixels | Year |
|---|---|---|---|---|
| iPhone 18 Pro Max | 440×956 | 3 | 1320×2868 | 2026 |
| iPhone 17 Pro Max | 440×956 | 3 | 1320×2868 | 2025 |
| iPhone 16 Pro Max | 440×956 | 3 | 1320×2868 | 2024 |
Check your site at 440 × 956
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Designing for 440px wide
Breakpoints
Tailwind: base styles only (below sm, 640px). Bootstrap: xs. Sideways (956px): Tailwind md (sm: md: styles apply).
Room for content
408px with 16px side padding, 392px with 24px. Anything fixed wider than 440px makes the page scroll sideways (how to fix it).
All devices 440px wide, whatever their height.
Nearby sizes
Questions people ask
Which phone have a 440 × 956 viewport?
iPhone 18 Pro Max, iPhone 17 Pro Max, iPhone 16 Pro Max.
Is 440 × 956 the screen resolution?
No, it’s the viewport in CSS pixels. The physical screen has more pixels: the iPhone 18 Pro Max is 1320 × 2868 (DPR 3); the iPhone 17 Pro Max is 1320 × 2868 (DPR 3).
Which breakpoint does a 440px wide screen use?
Tailwind CSS: base styles only (below sm, 640px). Bootstrap: xs.
Guides that help
- What is a viewport? CSS pixels vs screen resolutionA viewport is the area your page is laid out in, measured in CSS pixels, not screen pixels. See real numbers from iPhones and MacBooks, then check yours.Guides · 8 min read
- How to fix horizontal scrolling on mobile (12 causes)Page wobbles sideways on phones? The 12 usual causes of horizontal scrolling on mobile, a fix for each, and a console snippet that finds the culprit fast.Fixes · 9 min read
- Responsive breakpoints in 2026 — the widths that matterWhere 123 real phones, tablets, laptops and monitors land in CSS pixels, which responsive breakpoints actually matter in 2026, and which screens to test.Guides · 8 min read