iMac 24″ (4.5K) viewport size
2240 × 1260CSS px · 2× DPR · 4480×2520 physical
By default the iMac 24″ (4.5K) gives a full-screen web page a 2240 × 1260 CSS pixel viewport, drawn on a 4480 × 2520 pixel panel (device pixel ratio 2). That’s the size your media queries see, and it changes if the owner picks a different scaling option (listed below).
See your site on an iMac 24″ (4.5K)
Paste your address (or localhost:3000). doesitfit shows it at exactly 2240 × 1260, with Chrome (macOS)’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 2240 × 1260, but the browser’s own bars take some of it. In Chrome (macOS) a page gets about 2240 × 1149 on first load (24px menu bar and Chrome’s 87px tab strip + toolbar, maximized window, Dock hidden). That’s your real “above the fold”.
| Setting | Width | Height |
|---|---|---|
| Full viewport | 2240px | 1260px |
| Visible on first load (Chrome (macOS)) | 2240px | 1149px |
What it means for your CSS
Breakpoints
At 2240px: Tailwind uses 2xl (sm: md: lg: xl: 2xl: styles apply); Bootstrap uses xxl.
Content width
With 16px of padding on each side your text column is 2208px; with 24px it’s 2192px. Text closer than 8px to the edge looks cramped (more).
Sharp images
A full-width image needs about 4480px of real pixels (2240 × 2).
<img src="hero-4480.jpg" srcset="hero-800.jpg 800w, hero-4480.jpg 4480w" sizes="100vw" alt="…">
Styles for this width
Content-first breakpoints beat device lists, but if something breaks at this width:
@media (max-width: 2240px) {
/* screens 2240px wide and narrower */
}Other display size settings
The scaling the owner picks changes the viewport your site gets:
| Setting | CSS viewport |
|---|---|
| Default (default) | 2240 × 1260 |
| Larger text | 1920 × 1080 |
| More space | 2560 × 1440 |
How common is 2240 × 1260?
2240 × 1260 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.
Everything about the 2240 × 1260 viewport · All Monitors sizes
Questions people ask
What is the viewport size of the iMac 24″ (4.5K)?
2240 × 1260 CSS pixels, with a device pixel ratio of 2. The screen itself is 4480 × 2520 physical pixels.
How much of the iMac 24″ (4.5K) screen does a web page get in Chrome?
About 2240 × 1149 on first load: the 24px menu bar and Chrome’s 87px tab strip + toolbar, maximized window, Dock hidden. Design your first screen for that height, not the full 1260px.
Which CSS breakpoint does the iMac 24″ (4.5K) fall into?
At 2240px wide, Tailwind CSS uses 2xl (sm: md: lg: xl: 2xl: styles apply) and Bootstrap uses its xxl tier.
How wide should images be for the iMac 24″ (4.5K)?
A full-width image needs about 4480px of real pixels (2240 CSS px × DPR 2) to look sharp. Use srcset so smaller screens don’t download it.
How can I test my website on an iMac 24″ (4.5K) without one?
Open doesitfit.lol, paste your address (localhost works too) and pick the iMac 24″ (4.5K). It shows your site at exactly 2240 × 1260 CSS pixels and flags anything that spills past the edge.
Guides that help
- MacBook screen resolution vs CSS pixels, every modelA MacBook Air 13 has a 2560×1664 panel but websites see 1470×956. Panel vs CSS sizes for every MacBook, scaling options and real Chrome viewport heights.Devices · 7 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
- Most common screen resolutions in 2026 (real data)StatCounter's August 2026 figures for the most common desktop, mobile and tablet screen resolutions, what they really measure, and which sizes to test.Data · 7 min read
About these numbers
Confidence: High: confirmed by more than one independent source.
Sources include DeviceAtlas, Chrome DevTools device list (EmulatedDevices.ts), iosref.com, ios-resolution.com. Researched September 2026.