Full-screen solid colors to find dead pixels, stuck pixels and backlight bleed on a monitor, laptop or phone.
Every pixel on a screen is made of three subpixels (red, green and blue). A dead pixel stays off and shows as a black dot on a light background. A stuck pixel stays lit in one color, and a hot pixel stays white. Because each fault only stands out against certain colors, the test shows solid colors full screen, one at a time. Black reveals stuck or hot pixels and backlight bleed at the edges. White reveals dead pixels. Red, green and blue reveal subpixels that do not light. The gray and color ramps help you spot banding, and the 1 pixel checkerboard helps you notice ghosting and addressing faults. Stuck pixel mode cycles colors in a small area you drag over the dot. It only works in some cases and never flashes more than 3 times per second, the photosensitivity safety limit used by WCAG.
Paste the code into your HTML and the tool shows up on your page, without J-Kit's navigation and ads. It still runs in the browser of whoever visits your site.
<iframe
src="https://jkit.tools/embed/en-US/dead-pixel-test"
width="100%"
height="600"
style="border:0"
loading="lazy"
title="Dead Pixel Test"
></iframe>These references help contextualize formulas, standards, APIs and limitations used on this page. They do not replace professional validation when a result has legal, financial, medical or operational impact.
A dead pixel is always off (black). A stuck pixel is always lit in one color, usually red, green or blue, because one subpixel does not change. A hot pixel is always white. In every case the dot does not follow the screen color, which is exactly what the test reveals.
Look for dots that do not change color.
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