Dead pixel test
Fill your whole screen with solid colors to spot dead pixels, stuck pixels and uneven backlight. Ideal for a new monitor, laptop or phone.
Fill your screen with solid colors and look for dots that don’t match.
Clean the screen first. Click, tap or press Space for the next color; Esc to exit.
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What is a dead pixel?
Every pixel on an LCD or OLED screen is made of three subpixels: red, green and blue. A dead pixel has failed and stays dark on any color, so it shows as a black dot on white. A stuck pixel has one or more subpixels stuck on, so it shows as a bright red, green, blue or white dot, easiest to spot on black. Stuck pixels can sometimes be revived; dead pixels usually can’t.
How to run a dead pixel test
- Wipe the screen with a dry microfiber cloth, so dust isn’t mistaken for a pixel.
- Press Start dead pixel test. The screen fills with black.
- Look across the whole screen from about arm’s length, then up close where you see anything odd.
- Click, tap or press Space to go through white, red, green, blue and gray. Press Esc to exit.
What you might find
| What you see | Best color to spot it | What it is |
|---|---|---|
| Black dot | White | Dead pixel: always off. |
| Bright or colored dot | Black | Stuck pixel or subpixel: always on. |
| Glow along the edges | Black, in a dark room | Backlight bleed, common on LCD screens. |
| Blotchy patches | Gray | Uneven backlight or panel uniformity. |
Monitor, laptop and iPhone dead pixel test
On a monitor or laptop, the test goes full screen; check from arm’s length, then up close. On an iPhone or iPad, Safari can’t hide its toolbars completely, so scroll the colored screen slightly or rotate the phone to check the edges too. OLED phones show dead pixels as black dots on every color except black, where every pixel is off.
Dead pixel fix: what to do if you find one
- New screen: check the store’s return policy and the manufacturer’s pixel policy straight away.
- Stuck pixel: try a pixel-fixing video over the spot for 10–20 minutes. Avoid this if you are sensitive to flashing lights.
- Dead pixel: usually permanent. One dead pixel near the edge is often unnoticeable in everyday use.
FAQ
How do I check my screen for dead pixels?
Clean the screen, press Start dead pixel test and look closely at each solid color: black, white, red, green, blue and gray. Click or press Space to move to the next color. A dot that doesn't match the color around it is a dead or stuck pixel.
What is the difference between a dead pixel and a stuck pixel?
A dead pixel is always off, so it shows as a black dot, easiest to see on white. A stuck pixel is always on in one color, often red, green or blue, easiest to see on black. Stuck pixels can sometimes be revived; dead ones usually can't.
Can I fix a stuck pixel?
Sometimes. Pixel-fixing videos that flash colors rapidly over the spot for 10–20 minutes, or gentle pressure with a soft cloth while the screen is off, revive some stuck pixels. Flashing colors can trigger seizures in people with photosensitive epilepsy.
How many dead pixels are acceptable?
It depends on the manufacturer's pixel policy. Many allow a few dead pixels before a replacement, while some premium brands replace a monitor for a single one. Test a new screen right away so you're inside the return window.
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