Backlight Bleed & IPS Glow Test
This free tool fills your monitor or laptop screen with solid black and dark shades in full-screen, making backlight bleed, clouding, and IPS glow easy to spot around the edges. It runs entirely in your browser; nothing is uploaded.
Best viewed in a dark room. Turn screen brightness up and dim the room to spot light leaking at the edges and corners (backlight bleed) or corner glow on IPS panels (IPS glow).
100% local — nothing leaves your device
How to use it
- 1 Dim your room and set screen brightness to a high or normal level for the most visible results.
- 2 Click the test to fill your screen with solid black, then press the full-screen button to remove all borders.
- 3 Look at the edges and corners for glowing, lighter patches (bleed) or a hazy corner shift (IPS glow).
- 4 Cycle through the darker gray shades to check uniformity, then press Esc to exit.
Troubleshooting
Black screen isn't fully black on Windows 11
Disable any night light, HDR, or auto-brightness in Windows 11 Settings before testing, as these tint the panel. Also turn off ambient light sensors and adaptive brightness in your display driver. A true backlight bleed test needs a steady, uniform black with no software color shifting active.
Can't tell backlight bleed from IPS glow
Backlight bleed appears as bright, often yellowish patches near the edges or corners that stay visible from straight on. IPS glow is a silvery or warm haze in the corners that changes or fades as you move your head or shift viewing angle. Glow is normal on IPS panels; significant bleed is a defect.
Full-screen button does nothing in Chrome
Chrome blocks full-screen until you interact with the page, so click anywhere on the test first, then press the full-screen button. If it still fails, check the site permissions icon in the address bar and allow full-screen, or press F11 to toggle browser full-screen manually.
Edges look bright but it might just be reflections
Turn off room lights and close curtains so no external light reflects on the glossy panel. View the screen straight on from about arm's length. Genuine backlight bleed stays in the same spot as you move; reflections move with the light source and shift when you change your position.
Frequently asked questions
What is a good amount of backlight bleed?
Some bleed is normal, especially on edge-lit IPS and VA panels. Minor, even glow that you only notice in a dark room with a pure black screen is acceptable. Bright, uneven patches or flashlighting in the corners that are obvious during dark scenes usually indicate a defective unit worth returning.
Is backlight bleed the same as IPS glow?
No. Backlight bleed is light leaking through the panel edges, fixed in place and often colored. IPS glow is a viewing-angle effect that brightens the corners and shifts as you move your head. Glow is inherent to IPS technology, while excessive bleed is a manufacturing fault.
Does this test upload my screen or any data?
No. The test runs entirely in your browser using local code that simply displays black and dark gray colors full-screen. Nothing is captured, recorded, or uploaded, and no permissions are required. You can even run it offline once the page has loaded.
Can I run a backlight bleed test on my phone?
Yes. The test works on phones and tablets too. Tap to fill the screen with black, then view the edges in a dark room. OLED phones rarely show bleed since pixels emit their own light, but LCD phones can still reveal edge bleed and uneven backlighting.
Can I fix backlight bleed myself?
Mild bleed sometimes eases as a new panel settles over weeks. Gentle pressure fixes are risky and can damage the screen, so they are not recommended. If bleed is severe and the device is new, the best fix is to request a replacement or warranty exchange from the seller.