Screen & Monitor Tester
Diagnose your display for dead pixels, stuck subpixels, color uniformity, gradient banding, contrast dynamic range, and motion blur ghosting in full screen.
🖥️ Screen & Monitor Tester
Diagnose your display for dead pixels, stuck subpixels, color uniformity, gradient banding, contrast dynamic range, and motion blur ghosting in full screen.
Click anywhere to cycle colors (or press Space / Arrow keys)
Color: Black
📖 How to Thoroughly Test Your Computer Monitor or TV
Dead Pixel vs. Stuck Pixel
A dead pixel is completely dark (transistor permanently turned off). A stuck pixel is locked onto a single primary color (red, green, or blue). Stuck pixels can often be revived using high-frequency rapid flashing.
Detecting Black Crush on OLED and VA Panels
Many displays suffer from 'black crush', where the darkest near-black dark gray squares blend invisibly into pure black. Calibrating your gamma curve helps reveal lost shadow detail in dark gaming scenes and movies.
Motion Ghosting & Overdrive Settings
Fast-moving blocks reveal monitor pixel response time. If you see dark trailing streaks behind light objects, decrease your monitor's overdrive setting (e.g. from 'Extreme' to 'Fast') to eliminate inverse overshoot artifacts.
❓ Frequently Asked Questions
How do I spot a dead or stuck pixel?
Enter full screen mode and cycle through black, white, red, green, and blue. A dead pixel will show as a tiny black speck on white/red/green/blue backgrounds. A stuck pixel will glow brightly on a black background.
Can stuck pixels really be fixed by flashing?
Yes, rapid subpixel color cycling exercises the liquid crystal molecules and micro-transistors, often unsticking them after several minutes of continuous operation.
Does this test support high refresh rate monitors (144Hz, 240Hz, 360Hz)?
Yes! The motion blur ghosting test syncs with your browser's `requestAnimationFrame`, rendering smoothly at your monitor's exact native refresh rate.
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