Backlight Bleed Test
Turn off the lights, set brightness to your usual level and press Start. Light leaking at the edges is backlight bleed.
Click or press → for the next colour, ← to go back, Esc to exit.
How to Use the Backlight Bleed Test
LCD screens use a backlight, and some of that light can leak around the edges of the panel. On a black screen in a dark room, it shows up as bright patches in the corners or along the sides. This test shows pure black and near-black so you can judge how bad it is.
- Darken the room. Turn off the lights.
- Use normal brightness. Max brightness makes every panel look bad.
- Start full screen. Look straight at the centre.
- Move your head. IPS glow changes with angle, bleed does not.
Backlight Bleed vs IPS Glow
| Backlight bleed | IPS glow | |
|---|---|---|
| Looks like | Bright patches at edges or corners | A silvery sheen in corners |
| Changes with angle? | No | Yes, a lot |
| Normal? | A little is common | Normal on IPS panels |
How to Reduce Bleed
- Lower the brightness.
- Use bias lighting behind the monitor.
- If it is severe on a new monitor, return or exchange it.
OLED Screens
OLED has no backlight, so it can't bleed. A black screen should look perfectly black.
Frequently Asked Questions
Is some bleed normal?
Yes, a little is common on IPS and VA panels.
Can I fix backlight bleed?
Usually not fully. A return or exchange is the real fix.
Should I test with the lights on?
No. Test in a dark room for an honest view.
Does it get worse over time?
Usually not. Some panels improve slightly in the first weeks.
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