Monitor Contrast and Black-Level Test
Use stepped dark and bright reference blocks to check whether nearby shadow and highlight levels remain distinguishable.
Graduated patches show whether display settings crush blacks, clip whites, or hide detail near the ends of the brightness range. Use a neutral picture preset, disable strong dynamic contrast, set comfortable room lighting, and adjust brightness or contrast only when patches disappear.
What does this test measure?
Graduated patches show whether display settings crush blacks, clip whites, or hide detail near the ends of the brightness range.
Why is this test important?
Use stepped dark and bright reference blocks to check whether nearby shadow and highlight levels remain distinguishable.
How do you run the test?
Use a neutral picture preset, disable strong dynamic contrast, set comfortable room lighting, and adjust brightness or contrast only when patches disappear.
How should results be interpreted?
Every intended step should remain distinguishable without turning black into gray or clipping bright regions into one block.
Normal and problematic results
Every intended step should remain distinguishable without turning black into gray or clipping bright regions into one block.
Technical limitations
This visual tool does not measure a numeric contrast ratio and cannot replace a calibrated light meter.
Why can the score decrease?
Unstable measurements, denied permissions, unsupported browser APIs, background load, power saving, or an incomplete test can affect the result. When a score changes, the result screen explains the reason.
What should you do if a problem is found?
Reset black level, limited/full RGB range, contrast, brightness, HDR, and local dimming settings, then retest with known content.
Example Result Explanation
Frequently Asked Questions
What is contrast ratio in practice?
It is the difference between the brightest white and the darkest black a panel can show at the same time. High contrast is what makes images look deep rather than washed out, and it matters more to perceived quality than brightness alone.
I cannot separate the darkest steps. Is that normal?
Losing the first step or two is common, especially in a lit room. Losing several means black level is set too high or brightness too low. Adjust until the darkest bars are just distinguishable without the black field turning grey.
Why do the dark steps change when I move my head?
Shadow detail is the most viewing-angle sensitive part of an LCD image. Judge contrast from directly in front, since off-angle results tell you about the panel type rather than its real contrast.