Online diagnostic tool

Stuck Pixel Exerciser

Place a rapidly changing color patch over a suspected stuck pixel. This cannot repair physically dead pixels and results are not guaranteed.

Direct answer

What is the Stuck Pixel Exerciser Online?

Use a movable flashing color patch to exercise a suspected stuck pixel. Free browser-based tool.

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

Safety: Keep brightness moderate, avoid staring at flashing colors and stop if you feel discomfort. A dead pixel is usually a hardware defect; this tool is intended only for potentially stuck pixels.

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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 ExerciserExercise a suspected stuck-pixel area with changing colors. 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.