स्क्रीन टेस्ट.

Values are those reported by the browser and can be rounded, affected by zoom or limited for privacy. Refresh rate is measured from animation frames and can be lower with power saving, variable refresh rate or background tabs. Patterns are visual aids, not calibration.

Screen, matchMedia and requestAnimationFrame APIs are read locally. Sharpness patterns are drawn at device-pixel resolution, and gradients use exact 8-bit steps to reveal banding. Nothing is sent from this page.

A 4K monitor at 150% scaling reports 2560 × 1440 CSS pixels with a pixel ratio of 1.5, estimated as 3840 × 2160 physical pixels.