Dead Pixel Test
Click, tap or press → / Space for the next screen, ← to go back, Esc to leave. Clean the screen first - dust looks just like a dead pixel.
Test screens
Dead pixel: always black. Stuck pixel: always red, green, blue or another colour. Hot pixel: always white. Look closely on each screen, from about 30 cm (1 ft).
Your screen
- Resolution
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- Aspect ratio
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- Pixel ratio
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- Browser window
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- Refresh rate
- Measuring…
- Colour depth
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- Colour gamut
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- HDR
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Resolution is what the browser reports. With several monitors it is the screen this window is on. Measured from the browser's frame rate. Battery saving or a background tab can lower it.
Stuck pixel flasher
A small square that flashes red, green, blue, white and black very fast. Drag it over a stuck pixel and leave it for 10-30 minutes; it sometimes frees a stuck sub-pixel. It cannot repair a dead (always black) pixel.
⚠️ Warning: rapidly flashing colours. Do not use or watch it if you are sensitive to flashing light or have photosensitive epilepsy.
Check a monitor, laptop, TV or phone for dead, stuck and hot pixels, backlight bleed and banding with full-screen colours - plus resolution, HDR and refresh rate.
Fill your screen with pure black, white, red, green, blue and other test screens to find dead, stuck and hot pixels, then check backlight bleed, uniformity, banding and sharpness. It works on monitors, laptops, TVs with a browser, tablets and phones, ideally before the return window of a new screen closes. The page also shows your resolution, pixel ratio, colour gamut, HDR support and measured refresh rate, and works out pixel density from the screen size. Everything happens in your browser.