ToolsFree browser-based screen test

Gray Uniformity Test for OLED TVs and Monitors

Compare fullscreen 5%, 20%, and 50% gray fields to check dirty screen effect, edge shading, and uneven tint on TVs and monitors.

Panel tests
Test workspace

Use every mode and inspect the entire panel, including corners and edges.

Test pattern

Fullscreen controls hide automatically. Move the pointer or tap to bring them back; Escape exits.

Gray presets

Percentages describe the 0–255 RGB signal, not screen brightness or measured light output. These SDR patterns depend on browser color management and display settings.

F toggles fullscreen. Arrow keys switch modes. Escape exits.

How to use this test

How to test gray screen uniformity at 5% and 50%

01

Keep the viewing conditions steady

Clean the panel and sit directly in front of it. Disable automatic brightness and color filters, and use the same picture mode for every gray level.

02

Inspect a uniform 50% gray field

Enter fullscreen at 50% and wait for the controls to hide. Scan the center, corners, and edges for fixed clouds, darker areas, or pink and green tint.

03

Compare dark and mid-gray screens

Repeat at 5% and 20%. Check whether the same shapes remain fixed, then compare with a sports pan or another scene with a large even background.

What the result can tell you

Dirty screen effect versus OLED near-black unevenness

Mid-gray fields can reveal a dirty-screen appearance or edge shading; low gray can expose OLED near-black variation. This is a visual comparison, not a measurement of uniformity percentage or color error.

Testing notes

The field contains one RGB value everywhere. Any visible pattern is not deliberately drawn by the tool.

Viewing angle and room reflections can change apparent shading. Repeat from a centered position.

If an area follows your gaze or a reflection, change room lighting before blaming the panel.

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Compare smooth gray ramps, deliberate grayscale steps, and uniform fields to distinguish gradient posterization from fixed panel banding.

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Burn-In Test

Run solid colors, moving bars, checkerboards, and gradient sweeps to reveal image retention or uneven pixel aging.

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Backlight Bleed Test

Display black and low-gray fields in a dark room to distinguish edge bleed, clouding, IPS glow, and uneven backlighting.

Gray uniformity and dirty screen effect questions

Which gray level should I use for a TV uniformity test?

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Start with 50% for broad shading and tint, then compare 20% and 5% for darker unevenness. Keep display brightness and picture mode consistent.

Can this test calculate a uniformity score?

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No. A browser cannot measure light emitted from different areas of the panel. Quantitative luminance and color comparisons require a suitable meter.