Output
Steady colors, steps or fine-line patterns
UserBenchmark / All Tools / Black Level Test
Display
Black Level Test
Inspect near-black steps to find crushed shadow detail.
Free to useNo downloadNo sign-up
Black Level Test · At a glance
Quick answer: Inspect near-black steps to find crushed shadow detail. Merged dark steps can indicate crushed shadows.
Black Level Test
The test loads when you open it. Device access is requested only after you choose to start.
Detailed guide
How to use this tool
- Inspect near-zero grayscale steps.
- Adjust black-level controls carefully so dark detail remains visible without lifting black excessively.
Input
Manual visual inspection
Browser requirement
Native resolution; fullscreen support
Processing
Runs on your device; no tool-result upload
How it works and what the result means
These are visual inspection patterns. The page cannot read individual panel pixels, measure nits or contrast ratio, diagnose a panel automatically, or repair dead pixels.
Reading the result
Merged dark steps can indicate crushed shadows. Reflections and ambient light can hide them even when the source signal is correct.
Worked example and assumptions
RGB steps near zero
Check whether near-black patches remain distinguishable. Ambient reflections, limited-range output or monitor black-level settings may hide the darkest patches.
Check whether near-black patches remain distinguishable. Ambient reflections, limited-range output or monitor black-level settings may hide the darkest patches.
What to check next
Check RGB range agreement between source and display. Compare at normal room light before making an extreme adjustment.
Use native screen resolution and 100% browser zoom for fine patterns. Disable adaptive brightness for comparisons. PWM inspection needs an external camera; banding can also be a camera artifact.
Frequently asked questions
Should every near-black step always be obvious?
Visibility depends on panel contrast and viewing conditions. The goal is sensible shadow separation for the actual environment, not an arbitrary brightness boost.
How do I start the Black Level Test?
Choose a pattern and open fullscreen. Inspect the entire panel, then click to cycle patterns. Press Escape to leave fullscreen.
Does this tool require a download or an account?
No. Open the interactive tool above in a modern browser. The instructions and explanations are available even with JavaScript disabled; running a test needs JavaScript.
Why can two attempts give different results?
Power settings, background tasks, browser scheduling, operating-system input processing and device settings affect measurements. Compare repeated attempts with identical settings rather than the single highest score.