Full-Screen Colors & Light – Timers, 4K Backgrounds & Tests

Choose a screen color

Every color tool opens directly in full screen, can request Screen Wake Lock, supports long timers and offers downloadable backgrounds.

One color engine, several real uses

Display testing

Use exact white, black, red, green, blue and gray for pixel, uniformity, backlight and tint checks.

Light & camera backgrounds

Use warm white, pink, yellow, orange, purple and custom colors for simple fill light, webcam backgrounds and creative video.

10 hours and longer

Run 1h, 4h, 10h, 24h, 100h or no-limit sessions. Controls and cursor hide automatically until you interact.

4K & 8K downloads

Download flat PNG backgrounds in common desktop and mobile resolutions, or generate a selected shade locally.

Keep the screen awake when supported

The tools request the browser Screen Wake Lock API when you enable keep-awake mode. Browsers and operating systems may still deny or release the lock because of battery, thermal, visibility or policy conditions, so long sessions cannot be guaranteed on every device.

Screen videos on YouTube

Long-duration companion videos are available for several exact screen colors. They are useful on smart TVs, consoles and devices where opening the browser tool is less convenient.

Pure White · #FFFFFF Warm White · #FFF4E5 Red · #FF0000 Black · #000000 Green · #00FF00 Blue · #0000FF More on @MyChannel92

Direct answer

Why use several full-screen colors?

Different display defects become visible on different backgrounds. A complete visual check should include black, white, red, green, blue and gray rather than relying on only one color.

✓ Pixel inspection✓ Uniformity checks✓ No installation

Which screen color should you choose?

White

Best for dark pixels, dust, tint and brightness uniformity.

Black

Best for bright pixels, backlight bleed, glow and image retention.

Red, green and blue

Best for checking primary subpixel behavior and stuck pixels.

Gray

Best for dirty screen effect, banding and subtle color tint.

Frequently asked questions

Which color is best for finding dead pixels?

Use several colors. White is useful for dark pixels, black for bright pixels and light leakage, while red, green and blue isolate primary subpixel behavior.

Do these pages change hardware brightness?

No. They render a web color. Adjust physical brightness with your device or monitor controls.

Can screen color pages calibrate a display?

No. They are visual inspection utilities. Calibration and objective color measurement require appropriate hardware and reference software.

Explore more diagnostics

Choose another test

Move between screen, camera, audio and device checks without returning to the homepage.

View all tests

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.