FAQ

What is the difference between a dead pixel and a stuck pixel?

A dead pixel never lights up and appears as a permanent black dot on bright backgrounds. A stuck pixel is always lit and shows a fixed color (often red, green, or blue) even on a black screen.

How many dead pixels are acceptable?

This depends on the manufacturer. Many brands allow a small number of dead pixels (typically 1–3) before honoring a warranty replacement. Check your monitor's dead-pixel policy and attach an exported report as evidence.

Why should I test in fullscreen?

Windowed mode only tests the browser viewport area. Fullscreen ensures every pixel on the display is covered, which is essential for reliable detection.

Can this tool fix dead pixels?

No. This tool only detects and documents defects. Some stuck pixels can be fixed with pixel-exercise videos or gentle pressure, but dead pixels are usually permanent hardware failures.

Does the tool work on phones and tablets?

Yes, if your mobile browser supports fullscreen. Open the tool, enable fullscreen, and run the color test. Touch the screen to mark pixels.

Why does the test stop automatically?

After the last color or gradient in the sequence, the test ends automatically. You can also stop manually with Escape or the Stop Test button.

Will this damage my screen?

No. Displaying solid colors and gradients is safe and is a standard method used by monitor manufacturers for quality testing.

My marks disappeared after refreshing the page

Marked pixels during an active test are lost on refresh. Stop the test first to save results to history, or export the report before leaving the page.

Can I use this for OLED burn-in testing?

The color and gradient tests can help reveal burn-in (persistent image retention), but dedicated burn-in tests with static patterns run for extended periods are more thorough.

Which browsers are supported?

All modern browsers that support fullscreen API: Chrome, Firefox, Safari, and Edge.