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Backlight Bleed Test

Full-screen black, gray and white levels with a grid, to spot bleed, IPS glow and uneven patches.

  • Free, no sign-up
  • Runs in your browser
  • About 2 minutes

→ Space or tap: next← backG gridEsc exit

Before you start: dim the room, set brightness where you normally use it, and sit where you usually sit.

No full-screen mode in this browser. Safari on iPhone and some TV browsers can’t hide their bars, so the test fills the visible screen. Rotate the phone and scroll slightly to check the edges.

Result

What did you see?

Pick the one that matches best.

By GigaScreens Team · Updated 2026-10-17

Browser support: Tested in Chrome, Firefox and Safari (WebKit) on desktop and in iPhone and Android emulation. Real-phone checks are pending.

How to run the backlight bleed test

  1. Dim the room and set brightness to your normal level. Max brightness in a pitch-black room makes every LCD look worse than it does in daily use.
  2. Press Start. The screen goes black. Look at the edges and corners from your normal seat.
  3. Move your head left, right, up and down. Glow that shifts or fades is IPS glow. Patches that stay in the same place are bleed.
  4. Step through the grays with Next, tap or the arrow keys. Gray shows bands, tint and darker corners that black hides.
  5. Turn on the grid (G) to note where a patch sits, then answer “What did you see?”

Taking a photo for a return? Set the phone’s exposure so the photo looks like what you see. Backlight bleed looks ten times worse in a phone photo. Your camera is being dramatic.

Reading the result: glow, bleed or clouding

What you see Changes when you move? Normal?
IPS glow: silvery or tinted glow in the corners Yes, it shifts with viewing angle and distance Yes, on IPS panels
Backlight bleed: bright patches along an edge or corner No, it stays put A little is common. Heavy bleed is a defect
Clouding: blotchy patches toward the middle No Common on curved VA panels
Uneven uniformity: darker bands or a tint on gray No Varies a lot between units

Dell draws the same line in its IPS glow vs light leakage guide: glow changes with viewing angle and distance, while leakage stays fixed. DisplayNinja’s explainer covers clouding and flashlighting.

OLED screens have no backlight (Apple explains that each pixel makes its own light), so they can’t have backlight bleed. Glow on an OLED in a long-exposure photo usually comes from the camera.

Fix guide: what helps backlight bleed

  1. Lower the brightness. Bleed is light leaking past the panel, so less light means less bleed. DisplayNinja suggests this first.
  2. Add some room light. A lamp behind or beside the screen makes glow and mild bleed much less visible in dark scenes.
  3. Try local dimming if your monitor or TV has it. RTINGS tests black uniformity with local dimming on and off because it changes the result (their method).
  4. Leave the panel alone. Some guides suggest rubbing the area or loosening screws on the back. Pressure can damage the panel and opening anything can affect the warranty. We don’t recommend it.
  5. Use the return window. If bleed is obvious with the lights on and the monitor is new, return or exchange it. Bleed varies a lot between units of the same model.

What this test can’t measure

It shows test patterns. It can’t measure brightness, uniformity percentages or color accuracy. That needs a colorimeter, which we don’t use for this page. Your eyes, in your room, at your brightness, are the judge that matters for daily use.

Frequently asked questions

Is some backlight bleed normal?

A little bleed is common on LCD monitors, and IPS glow in the corners is normal for IPS panels. Bright patches you can see with the lights on, on a new screen, are worth a return or exchange.

How do I tell IPS glow from backlight bleed?

Show a black screen and move your head. IPS glow changes or fades with your viewing angle. Backlight bleed stays in the same place, as Dell’s support guide describes.

Can OLED screens have backlight bleed?

No. OLED pixels make their own light and there’s no backlight to leak. OLED screens can have other issues, such as burn-in or near-black uniformity problems.

How do I photograph backlight bleed for a return?

Use a black screen in a dim room and set the phone exposure so the photo matches what you see. Auto mode on a black screen exaggerates bleed a lot.

Does lowering brightness fix backlight bleed?

It doesn’t remove it, but it makes it less visible. Adding some room light helps too. If it’s still obvious in normal use on a new monitor, use the return window.

Sources