The professional tool to check and fix your screen for dead or stuck pixels, backlight bleed, and uniformity.
Cycle full-screen colors to spot dead or stuck pixels.
Reveal backlight bleed, IPS glow, and banding.
Run animated patterns to help revive stuck pixels.
No downloads; works on desktop and mobile.
A dead pixel test displays solid colors across your screen to identify defective pixels on monitors, laptops, TVs, and mobile devices. By cycling through white, black, red, green, and blue, you can spot dead pixels (permanently black), stuck pixels (fixed color), or backlight bleed. This browser-based test requires no installation—just open the page and start testing instantly on any device.
Our screen test uses your browser's fullscreen API to display solid colors across your entire monitor. When you click 'Start Screen Test', the tool cycles through pure colors (white, black, red, green, blue, cyan, magenta, yellow) one by one. Each color is rendered at maximum saturation to make pixel defects visible. You examine the display on each color—dead pixels appear as black spots, stuck pixels show as fixed color dots. All processing happens in your browser with no data collection.
This browser-based test accurately reveals most visible pixel defects when viewed in a dark room at maximum brightness. However, there are limitations: Very small sub-pixel defects may be hard to see without magnification. Backlight bleed is easier to spot on dark backgrounds. Color accuracy depends on your monitor's calibration. For warranty claims, manufacturers may require specific testing conditions or their own diagnostic tools.
Dead pixels appear as permanently black dots that don't change color regardless of the displayed image. They are usually permanent hardware defects. Multiple dead pixels may qualify for warranty replacement.
Stuck pixels remain fixed on one color (red, green, or blue) and don't respond to image changes. Unlike dead pixels, stuck pixels can sometimes be fixed using our Stuck Pixel Fixer tool.
Light bleeding from screen edges visible on dark colors indicates backlight bleed. Minor bleed is common on LCD/LED monitors. Severe bleed that affects normal viewing may warrant replacement.
Common questions about screen testing and pixel defects.
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Methodology: Our testing methodology uses standard Web APIs (Fullscreen API, Canvas) that are supported by all modern browsers. Tests are designed for accuracy and repeatability.
About: HardwareTest provides free, privacy-first hardware diagnostics. All tests run entirely in your browser with no data collection.
Disclaimer: This tool provides visual pixel inspection only. Results may vary based on viewing angle, brightness settings, and ambient lighting. For warranty claims, consult your monitor manufacturer's testing requirements.
Guides on dead pixels, backlight bleed, and display health.
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