Screen Info
View browser-reported screen, viewport, pixel-ratio, color-depth, media-query, and timing information.
This check runs directly on this page without requiring fullscreen. Review what this browser test can and cannot measure.
Before you start
- Move the browser window to the display you want to inspect.
- Use the display at its intended scaling and browser zoom.
How to run this check
- Open Screen Info tool
- Move the browser window to the display you want to inspect
- Record the reported CSS screen and viewport dimensions, device-pixel ratio, and color depth
- Treat browser media-query matches as capability signals rather than measured gamut coverage
- Enter the measured display diagonal if you want to calculate PPI
What this browser test can tell you
Can help you check
- CSS pixel dimensions, device-pixel ratio, color depth, and browser media-query signals.
Cannot measure
- Without user input, this test cannot determine physical size, PPI, model, or exact gamut coverage.
Setup, interpretation, and sources
Recommended setup
- Move the browser window to the display you want to inspect.
- Keep browser zoom and operating-system scaling in mind when recording the reported values.
How to interpret what you see
- Record the reported values together with browser zoom, scaling, browser, and display selection.
- Exact physical size, pixel density, and gamut coverage require manual dimensions plus calibrated measurement hardware.
Sources
Methodology reviewed:
Resolution
Pixel Density
Color Space
Browser Cadence
Browser Capabilities
Browser
📏 Measure Physical Size
The browser does not report physical size. Enter a measured diagonal to calculate a formula estimate from browser-reported CSS dimensions × DPR.
Enter a measured diagonal to calculate PPI.
Formula: √((CSS width × DPR)² + (CSS height × DPR)²) ÷ user-entered diagonal. Scaling and browser reporting can differ from the panel's native pixel matrix, so confirm exact specifications separately.
🔧 Technical Details
🔧 Common Issues & Solutions
🖥️ "Browser shows 1920x1080 but Windows says 2560x1440" (Logical vs physical resolution)
What the browser reports: window.screen uses CSS pixels, which can differ from the display mode shown by the operating system because of scaling and browser behavior.
Device-pixel ratio: DPR is a browser-exposed ratio used to map CSS pixels to device pixels. Multiplying CSS dimensions by DPR is useful context, but it is not guaranteed to equal the panel's native pixel matrix.
Next step: Record the CSS dimensions and DPR shown here, then confirm native resolution in operating-system or manufacturer documentation when exact panel specifications matter.
🔬 "Calculated PPI doesn't match monitor specs" (Marketing PPI vs actual)
Formula: PPI is pixel diagonal divided by physical diagonal in inches. This page uses CSS dimensions × DPR for the pixel dimensions and only calculates after you enter a measured diagonal.
Why values differ: The measured viewable diagonal, rounded specifications, operating-system scaling, DPR, and browser reporting can all change the inputs.
Next step: Measure the viewable diagonal carefully and keep the entered value with the result. Confirm native pixel dimensions separately for an exact physical PPI.
⚡ "Refresh rate shows 59.94Hz instead of 60Hz" (NTSC video timings)
What the browser reports: This card samples requestAnimationFrame cadence for a few seconds while the tab is visible.
Limitations: Browser scheduling, background load, power saving, tab visibility, graphics compositing, and the selected display can affect cadence. It is not exact signal timing.
Next step: Keep the tab visible and compare repeated runs under the same conditions. Confirm configured signal timing in the operating system or with dedicated hardware.
🌈 "HDR monitor but Windows doesn't detect HDR" (HDMI 2.0, cable, drivers)
What this page can show: Browser media-query matches and browser-visible values only. It does not verify that HDR is active or diagnose a hardware chain.
Context: Operating-system mode, browser support, GPU output, adapters, display settings, and color management can affect the signal.
Next step: Check the operating-system and manufacturer guidance for the exact hardware path. External certification and calibrated measurements must be confirmed separately.
🎨 "Browser says sRGB but monitor claims DCI-P3/Rec.2020" (Color space vs coverage)
What the browser reports: The CSS color-gamut media query indicates a browser/output capability signal for sRGB, P3, or Rec.2020.
Limitations: A match does not measure gamut coverage, color accuracy, active display mode, or which screen in a multi-monitor setup produced the signal.
Next step: Record the signal with browser, scaling, and display selection. Use a calibrated colorimeter or spectroradiometer for exact gamut coverage.