Screen Uniformity Test
Check for clouding, dirty screen effect (DSE), and brightness uniformity
Press F11 for fullscreen, then click to start
Clouding or DSE Found? Time for a Replacement
Backlight uniformity issues are baked into the panel — they don't fix themselves and tend to worsen with age. These three are tested for excellent panel uniformity.
LG UltraGear 27GR95QE OLED
27" QHD W-OLED. Per-pixel emission means no backlight to leak — no clouding, no DSE, ever.
View on AmazonDell UltraSharp U2723QE
27" 4K IPS Black. Dell's strict uniformity binning + zero-bright-dot policy is industry-leading for returns.
View on AmazonASUS ProArt PA279CV
27" 4K IPS, factory uniformity-corrected, Calman-verified. Solid mid-tier pick for color and uniformity.
View on AmazonAs an Amazon Associate we earn from qualifying purchases at no extra cost to you.
Quick Test Colors
Click any color to test, or use the main button for cycling mode
Common Issues to Check
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1.
Backlight Bleed
Light leaking from edges on black screen (corners especially)
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2.
IPS Glow
Silvery glow at angles, worst in corners on dark content
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3.
Clouding
Uneven brightness patches, visible on white/gray
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4.
Dirty Screen Effect (DSE)
Splotchy/smudged appearance on gray, common on VA panels
Best Test Colors For
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Black
Backlight bleed, IPS glow (dim room)
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Dark Gray (5-25%)
DSE, dirty screen effect (most visible)
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Mid Gray (50%)
Overall uniformity, banding
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White
Clouding, brightness uniformity, yellowing
Testing Tips
- Dim your room: Backlight bleed and IPS glow are most visible in dark environments
- Let monitor warm up: Run for 30+ minutes before testing for accurate results
- Test at normal brightness: High brightness exaggerates issues; test at your usual setting
- Move your head: IPS glow changes with viewing angle; backlight bleed doesn't
- Use the grid overlay: Press G to show a grid that helps identify uneven areas
Should I Return My Monitor?
Likely Acceptable
- - Minor IPS glow in corners (normal for IPS)
- - Slight brightness variation across screen
- - DSE only visible on specific gray test patterns
- - Minor backlight bleed only visible on pure black
Consider Returning
- - Bright spots/clouding visible in normal content
- - DSE visible during normal use (sports, games)
- - Severe backlight bleed affecting dark scenes
- - Yellow or pink tint in corners
Our Should I Return My Monitor tool can help you decide.
Uniformity by Panel Type
IPS Panels
Typically have IPS glow (silvery look at angles) and potential backlight bleed. Usually good brightness uniformity. IPS glow is a physical property, not a defect.
VA Panels
Prone to DSE (dirty screen effect) visible on gray backgrounds. Excellent black uniformity due to high contrast. Cloudiness less common than IPS.
TN Panels
Usually good uniformity but poor viewing angles cause apparent uniformity issues. Color shift at edges is normal, not a defect.
OLED Panels
No backlight bleed (pixels self-emit). May have near-black uniformity issues or slight color tint variations. Perfect when displaying true black.
