Your full screen resolution, viewport size, pixel ratio, color depth, and orientation — detected instantly from your browser. All processing is local, nothing is sent to our servers.
Your screen resolution is the total number of pixels your display can show — for example, 1920×1080 (Full HD) or 2560×1440 (QHD). This is a property of your monitor or display hardware.
Your viewport size is the area of the browser window where web content is displayed. It is always smaller than or equal to your screen resolution, because the browser window includes chrome (address bar, tabs, toolbars) that takes up space outside the viewport.
The device pixel ratio (DPR) is the ratio between physical pixels on your screen and logical (CSS) pixels. A DPR of 2 means your display has 2 physical pixels for every 1 CSS pixel — this is what Apple calls "Retina" and what high-DPI or HiDPI displays use.
High DPR displays (2x, 3x) render text and images at much higher quality than standard 1x displays. Web developers use the DPR value to serve appropriately sized images — for example, serving a 400px-wide image at 2x resolution actually displays at 200 CSS pixels but with twice the detail.