Screen Size Test – Resolution, Viewport & Pixel Ratio

Your display information

Physical screen size cannot be measured accurately by every browser. Values shown here describe browser-reported pixels and scaling.

Direct answer

What is the Screen Size Test?

Check screen resolution, viewport dimensions, scaling, pixel ratio and display information.

✓ No installation✓ Works in compatible browsers✓ Privacy-focused testing

Practical guide

Screen size, viewport and resolution are not the same thing

Web browsers can report pixel dimensions but usually cannot know the exact physical diagonal size of a display with certainty. This page therefore focuses on screen and viewport dimensions, device pixel ratio and related values that are reliable enough for web layout and troubleshooting.

For a more reliable result

Screen width and height are browser-reported display coordinates.
Viewport width and height describe the area currently available to the webpage.
Device pixel ratio indicates how CSS pixels map to the underlying display pixel density.
Physical inches or centimeters should be confirmed from the device specification when accuracy matters.

What this test cannot confirm

Do not treat a browser-based diagonal-size estimate as a hardware measurement. It can be affected by scaling, zoom and the information the operating system chooses to expose.

When browser screen values are useful

These values are especially helpful when a website looks unusually large or small, when testing responsive layouts, or when checking why screenshots and browser dimensions differ from the panel specification. For buying a monitor or replacement panel, use the manufacturer model specification for the physical diagonal size and native resolution.

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Complete Screen TestRun pixels, colors, uniformity, contrast, sharpness and motion in one guided check.Dead Pixel TestInspect solid colors for dead, stuck, bright or dark pixels.Touch Screen TestCheck touch coverage, dragging continuity and dead zones.Keyboard TesterTest a full-size keyboard and confirm every key press.Mouse TesterTest buttons, wheel, movement, dragging and double-clicks.Audio TesterCheck speakers, stereo channels, tones and microphone input.Camera & WebcamTest built-in, USB, phone, tablet and compatible TV cameras.Microphone TesterView microphone levels, waveform, recording and playback.Pixel ExerciserRun full-screen rapid color cycling for suspected stuck pixels.Gradient TestInspect gradients, tonal transitions and visible banding.Brightness & ContrastCheck black levels, white saturation and contrast separation.Screen Size TestView viewport, resolution, pixel ratio and display data.Text SharpnessInspect text rendering, browser scaling and clarity.Motion & GhostingObserve motion blur, ghosting and response behavior.Resolution & ScalingCheck screen resolution, CSS pixels and scaling.Device InformationReview screen, browser, hardware and platform information.Browser CapabilityCheck which browser APIs and hardware features are supported.Network TestCheck connection status, latency and estimated download speed.GPS & LocationTest browser geolocation, accuracy, altitude and speed.Sensor TesterTest orientation, motion, acceleration and rotation sensors.Multi-Touch TesterTrack multiple touch points, pinching and rotation gestures.Screen Color ToolsOpen full-screen colors with timers, lighting presets and 4K background downloads.Response Time TestObserve ghosting, blur and pixel-transition behavior at several speeds.Stylus Drawing TestCheck pen, touch, pressure, tilt and drawing continuity in your browser.