What’s my viewport size?
Your browser’s viewport right now, in CSS pixels: the size websites design for. Resize the window or rotate your phone and it updates.
Devices with a viewport like yours
Working it out…
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What these numbers mean
Viewport
The width and height in CSS pixels that a web page gets inside the browser window. Media queries, vw/vh and layouts all use it. What is a viewport?
Device pixel ratio
How many physical pixels make one CSS pixel. 2 or 3 on phones and Macs, 1 to 1.5 on many Windows screens. DPR explained
Questions people ask
What is my viewport size?
This page shows it live at the top: the width and height in CSS pixels that websites get in this browser window right now. It changes when you resize the window or rotate your phone.
Why is my viewport smaller than my screen resolution?
Screens pack several physical pixels into one CSS pixel (the device pixel ratio), and the browser’s toolbars, tabs and your operating system’s scaling take a share too.
What is the difference between innerWidth and screen.width?
window.innerWidth is the browser window’s viewport, including a scrollbar if there is one. screen.width is the whole screen in CSS pixels, whether or not the window fills it.