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Backlight Bleed Test

Check your monitor for backlight bleed. The test displays near-black screens at different brightness levels so you can spot light leaking from the edges or corners.

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Dim your room lights for accurate results. The test cycles through near-black screens.

How to use

  1. 1Click Start test to enter fullscreen. Dim the lights in your room first.
  2. 2A dark screen appears at different brightness levels. Look at the edges and corners.
  3. 3Light leaking from edges or corners indicates backlight bleed. Click or press Space, Enter or the right arrow to advance. Press Escape to exit.

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Understanding backlight bleed

What causes it and what to look for.

LCD monitors use a backlight (usually LEDs along the edges) to illuminate the liquid crystal layer. When the panel frame applies uneven pressure, light escapes around the edges and corners. This creates visible bright patches on dark screens, known as backlight bleed.

Bleed is most visible in dark rooms at high brightness settings. Games and movies with dark scenes (horror games, space environments, night sequences) make it particularly noticeable. If you only notice it during this test and not during normal use, it is unlikely to affect your experience.

Backlight bleed FAQ

Common questions about monitor light leaks.

Dim the lights in your room, display a fully black or near-black image in fullscreen, and look at the edges and corners of your monitor. Bright spots or glowing edges indicate backlight bleed. This test cycles through several low-brightness levels to make bleed easier to spot.
Minor bleed is considered normal for LCD monitors, especially IPS panels. Manufacturers typically only accept returns for severe bleed that significantly affects dark-scene viewing. Check your manufacturer's warranty policy for their specific threshold.
Backlight bleed can change slightly over time. Some users report it improving after a few weeks as the panel settles. In rare cases, physical damage or temperature changes can make it worse. It generally stays consistent after the initial break-in period.
Backlight bleed stays in fixed spots regardless of your viewing angle. IPS glow shifts position and intensity when you move your head. Glow is an inherent property of IPS panel technology. Bleed is a manufacturing variance caused by uneven pressure on the panel frame.
No. OLED pixels produce their own light, so there is no backlight to leak. OLED monitors can display perfect blacks. However, they can have different issues like burn-in and pixel uniformity variance.
Lower your monitor's brightness setting. In many cases, bleed is only noticeable at high brightness in a dark room. Some users gently loosen bezel screws to relieve panel pressure, but this can void your warranty and risk cracking the panel.

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