Screen Bleeding Test – Backlight Bleed & IPS Glow Checker

How to Use

Click Start Bleeding Test and your browser will go fullscreen
Dim your room lights for best visibility
Black screen — Look at corners and edges for white/grey light leaking through
Click or press any key to cycle through colors
Use red, green, blue to check color uniformity across the panel
Press Esc to exit the test

Click a Color to Test

BLACK

WHITE

DARK

RED

GREEN

BLUE

YELLOW

MAGENTA

CYAN

GREY

Pattern Tests

Horizontal Lines

Vertical Lines

Checkerboard

Vignette

Gradient

RGB Gradient

Bleed Severity Scale

None

Barely

Minor

Moderate

Severe

Some backlight bleed is normal on IPS and VA panels. Minor bleed in extreme corners is generally acceptable. Bleed that extends into the center of the panel during everyday use warrants a return/replacement.

Black Test The most important. Any bright spots on black = bleed or IPS glow.

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White Test Look for dark spots or uneven brightness (clouding/mura defects).

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Solid Colors Check if red/green/blue are uniform across the panel — no dim patches.

Dim Your Room Backlight bleed is only visible in dark conditions — test in a dim room.

What is Screen Bleeding and Why Does it Affect Monitors?

Screen bleeding, commonly referred to as backlight bleed, is a widespread issue found in many modern liquid crystal displays (LCDs). It occurs when the light from your monitor's backlight improperly leaks around the edges or corners of the panel, creating noticeable bright patches in areas that should otherwise appear pitch black. Because LCD panels rely on a constant backlight shining through liquid crystals to display imagery, perfectly blocking that light is extremely difficult from a manufacturing standpoint. This defect is particularly visible when you are playing games with dark scenes, watching movies with letterbox black bars, or using your computer in a dimly lit room. While practically all edge-lit displays and IPS panels exhibit some minor degree of light leakage, severe backlight bleed can ruin contrast, destroy immersion, and be highly distracting to the human eye. Performing a screen bleeding test helps you identify if the light leakage on your specific unit is within acceptable manufacturing tolerances or if you should seek a replacement.

Understanding the Difference Between Backlight Bleed and IPS Glow

While they look similar, backlight bleed and IPS glow are distinct phenomena. Backlight bleed usually appears as concentrated yellow or white light leaking directly from the bezel's edges, regardless of your viewing angle. IPS glow, however, is an inherent characteristic of In-Plane Switching technology. It typically manifests as a hazy, bronze or silvery glow that shifts in intensity and color as you move your head or change your viewing angle in front of the display.

How to Properly Conduct a Screen Bleeding Test at Home

Conducting an accurate screen bleeding test requires the right environment and testing tools to ensure you aren't misdiagnosing reflections or ambient light as monitor defects. First, you must completely eliminate ambient room lighting by turning off your lamps and closing all window blinds—the room should be as close to pitch black as possible. Next, adjust your computer monitor's brightness setting to a realistic level; testing at 100% brightness often exaggerates the appearance of bleed and isn't representative of typical daily usage. We recommend setting your brightness between 30% and 50% for standard evaluations. Once your environment is prepped, launch our pure black solid color test screen in fullscreen mode. Sit directly in front of the center of your monitor at your normal viewing distance. Look closely at the four corners and the outer edges of the screen for any bright, uneven patches of light breaking through the darkness.

Using Additional Colors to Test for Screen Uniformity

While black screens are essential for spotting backlight leakage, flipping through pure white, red, green, and blue test patterns helps evaluate your panel’s overall color uniformity. A white screen test easily reveals dirty screen effect (DSE), clouding, or darker tinted regions near the center of the display. Exploring solid RGB colors allows you to quickly spot stuck or dead pixels that might be jammed on a specific sub-pixel color, ensuring your monitor is functioning flawlessly.

What to Do if Your Monitor Fails the Screen Bleeding Test

If you've run the screen bleeding test and discovered significant light leakage creeping into the center of your display, you have a few options to consider. First, try gently massaging the bezel framing the screen with a microfiber cloth; sometimes, bleed is caused by uneven pressure from the plastic frame housing the panel. If the bleeding persists and is severe enough to distract you during regular gameplay or movie watching, you should check your monitor's warranty status or return window. Most manufacturers acknowledge that minor corner bleed is normal, but they will accept RMAs (Return Merchandise Authorizations) for severe cases that impact the center of the screen. When requesting a replacement or refund, be sure to take clear photographs of your monitor displaying the black test pattern in a dark room; this photographic evidence will speed up the customer support process and validate your claims.

Can Local Dimming Settings Reduce Backlight Leakage?

Yes. If your TV or premium monitor supports Full-Array Local Dimming (FALD) or Mini-LED technology, enabling it can dramatically diminish perceived backlight bleed. Local dimming allows the monitor to independently shut off specific backlight zones behind dark areas of the image, physically preventing light leakage and delivering deep, true blacks. If your display offers this feature, testing the screen with local dimming both enabled and disabled will immediately highlight its contrast-enhancing capabilities.

Frequently Asked Questions

Yes. Almost all edge-lit IPS and VA panels exhibit some degree of backlight bleeding or IPS glow due to the way they are manufactured. Minor light leakage in the extreme corners is generally considered normal and acceptable as long as it doesn't distract you during ordinary use.

Generally, no. Screen bleeding is a physical manufacturing artifact that is present out-of-the-box. While it shouldn't progressively worsen, extreme changes in temperature or physically moving and bumping the monitor can occasionally cause the bezel to warp slightly, which might marginally alter where the bleeding appears.

There is no software fix for backlight bleed since it is a physical hardware defect. Sometimes, gently massaging the edges of the screen with a very soft microfiber cloth can relieve uneven pressure from the plastic bezel, mildly reducing the bleed. However, if the light leakage is severe, the only real solution is to return the monitor under warranty for a replacement.

Backlight bleed typically looks like distinct flashlights or hotspots shining directly from the edges of the bezel, and its appearance doesn't change when you move your head. IPS glow, on the other hand, is a hazier, yellowish or silvery glow across the panel that shifts in intensity and color depending on your viewing angle.