Dead Pixel Test

Show full-screen solid colors to find dead or stuck pixels on a monitor or phone.

Start the test to fill the whole screen with one solid color at a time. Click, tap or press Space or the arrow keys to move to the next color. Press Esc to exit.

How to find dead or stuck pixels

Look slowly across the screen on each color. On the black screen, look for points of light: those are stuck or "hot" pixels, and bright patches near the edges are backlight bleed. On white, look for dark dots, which are dead pixels. The red, green and blue screens reveal faults in individual sub-pixels that are invisible on white.

When to run the test

Run it as soon as you unbox a new monitor, laptop, phone or TV, while the return period is still open, and before buying a used device.

Frequently asked questions

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

A dead pixel stays black on every color because it gets no power. A stuck pixel stays lit in one color (red, green or blue) because a sub-pixel is permanently on. Stuck pixels sometimes recover; dead pixels usually do not.

Can a dead pixel be fixed?

A truly dead pixel is a hardware fault and normally needs a panel replacement. A stuck pixel can sometimes be revived by rapidly cycling colors over it for several minutes. Check your warranty: many makers replace a screen only above a set number of faulty pixels.

How should I prepare the screen?

Wipe off dust first, set brightness high and view the screen straight on in a dim room. A speck that moves when you wipe it is dust, not a pixel.

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