Black Dead Pixel Test
A black dead pixel test fills your screen with pure black (#000000) to reveal bright defects — including stuck pixels lit in red, green, or blue, hot pixels that always glow white, and backlight bleed around screen edges. On a healthy display, the black screen should appear uniformly dark. Any bright spot is a defect. Black is the most revealing test color because bright anomalies stand out against total darkness.
Ready to scan your monitor
The test displays 6 solid colours in full-screen — Black, White, Red, Green, Blue, and Gray. Scan the entire screen for any pixel that doesn't match.
Click or → next colour · ← previous · Esc exit
What Do Bright Pixels on a Black Screen Mean?
| Defect Count | Rating |
|---|---|
| 0 defects | Perfect |
| 1 dead pixel | Acceptable |
| 2–5 defects | Borderline |
| 6–10 defects | Degraded |
| 11+ defects | Failing |
Frequently Asked Questions
What is a stuck pixel on a black screen?
A stuck pixel appears as a bright red, green, or blue dot on a black background. Unlike a dead pixel (which stays permanently off/black), a stuck pixel is locked in an 'on' state. Stuck pixels may respond to pixel-unsticking software (such as JScreenFix) which rapidly cycles colors to un-stick the pixel. Dead pixels are always dark and don't respond to any repair attempt.
What is backlight bleed?
Backlight bleed appears as a bright glow or cloudy patches along the edges or corners of the screen when displaying a pure black image. It's caused by light from the backlight leaking through the LCD layers. Minor bleed is normal for most IPS panels; OLED displays have zero backlight bleed since each pixel generates its own light. If bleed is severe enough to disrupt normal viewing, the panel may qualify for replacement under warranty.
How many bright pixels on black is acceptable?
ISO 13406-2 Class II (the most common panel standard) allows up to 2 Type 1 defects (always-on bright pixels) per million pixels. On a 1080p monitor (~2 million pixels), that's technically up to 4 bright defects. Most panel manufacturers allow 1–3 bright defects before warranty replacement. A single bright pixel in the center of the screen is more disruptive than 3 in a corner.
Can I fix a bright pixel that shows on a black screen?
Stuck bright pixels sometimes respond to pixel-cycling software: JScreenFix and PixelHealer rapidly flash the affected area through color cycles, which can discharge a stuck subpixel. Success rates are about 50% for recently stuck pixels. Apply the tool for 20–30 minutes. If the pixel doesn't respond after multiple sessions, it's likely a permanent hardware defect. Dead pixels (always dark) cannot be fixed by software.
Does IPS glow show up on the black test?
Yes. IPS glow is a silver or milky haze visible in the corners of IPS panels when the screen is dark. Unlike backlight bleed (bright edges), IPS glow appears as a shimmering overlay and varies based on viewing angle. A small amount is normal and inherent to IPS technology. It's most visible in dark rooms and when viewing the screen slightly off-axis. OLED displays do not exhibit IPS glow.
How do I use this black screen pixel test?
Click the 'Go Fullscreen' button to fill your display with pure black. View from your normal sitting distance in a dim room for best results. Look for any bright colored dots, glowing patches along edges (backlight bleed), or shimmering corner haze (IPS glow). Note the location of any defects. Press Escape to exit fullscreen. Repeat for other colors using the test switcher above.
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