High-density display
A reported screen of 1,440 × 900 CSS pixels with a DPR of 2 gives an estimate of 2,880 × 1,800 device pixels. Scaling or browser behavior can make that estimate differ from the native panel.
Reading browser display information…
Display properties are read locally using browser APIs. This tool does not upload its report.
How to use the Screen Resolution Checker
- 01
Read Layout viewport for the space currently available to a web page, measured in CSS pixels.
- 02
Compare the screen CSS dimensions and device pixel ratio. The estimated device-pixel figure multiplies these values; it is not a verified panel specification.
- 03
Resize the browser, move it to another monitor, or change zoom to inspect how measurements change. Use Refresh values if needed.
- 04
Copy the display report when documenting a layout issue. Include your browser zoom and operating system scale settings for context.
Examples
Responsive layout debugging
A laptop screen might report 1,920 × 1,080 CSS pixels while the browser viewport is only 1,100 × 760. Responsive page breakpoints depend on viewport space.
Pinch zoom on mobile
Pinch zoom can shrink the visible visual viewport while the layout viewport stays larger. Visual viewport scale helps explain that difference.
CSS pixels and device pixels
A CSS pixel is a web layout unit. Device pixel ratio expresses the relationship between device pixels and CSS pixels, and can reflect both display scaling and page zoom. Multiplying reported screen dimensions by DPR is useful as an estimate, but a browser cannot guarantee that the result matches the physical panel’s native resolution.
Screen, layout viewport, and visual viewport
Screen dimensions describe the display the browser considers current. Available screen dimensions usually remove operating system interface areas. The layout viewport describes the browser’s page area, including any scrollbar. The visual viewport describes the part currently visible, which can change with mobile pinch zoom or an on-screen keyboard.
What a browser cannot measure reliably
This checker does not measure physical inches, monitor diagonal, native panel resolution, refresh rate, or hardware model. Browser privacy features may round or simplify measurements. Multiple monitors, display mirroring, remote desktops, zoom, and operating system scaling can change the reported values. Check system display settings or manufacturer specifications when native resolution matters.
What to know
- Browser-reported dimensions are affected by zoom, scaling, privacy settings, and platform behavior.
- Native panel resolution, physical screen size, refresh rate, and hardware model are not measured.
Common questions
Is the estimated device resolution my monitor’s true resolution?
It may match in some configurations, but it is only screen CSS dimensions multiplied by device pixel ratio. Zoom, scaling, privacy rounding, and browser implementation can make it differ from the native panel.
Why is the viewport smaller than the screen?
The browser window may cover only part of the display. Browser controls and operating system UI also use space, so web content usually has a smaller usable area.
Can this tell my screen size in inches?
No. Browser measurements do not provide trustworthy physical dimensions. You need a known diagonal or physical measurement for a pixels-per-inch calculation.
Why do values change when I zoom?
Page zoom changes how CSS pixels relate to the display and can change device pixel ratio. Mobile pinch zoom often changes visual viewport dimensions and scale instead.