Screen contrast test
Click the pattern to run a full-screen black level test and white clipping test, then adjust brightness and contrast until the numbered steps stay separate.
Screen contrast test workspace
How to use
5 short steps.
Pick a standard picture mode
Write down your current settings, choose a standard or neutral mode, and turn off dynamic contrast.
Click the pattern to go full screen
Start with the black level steps in a dim room. The darkest patches should be hard to see, but not all the same.
Set brightness with the black level steps
Lower or raise the brightness or black level control until patch 1 is just visible against the background.
Set contrast with the white clipping steps
Press Space for the near-white steps. Lower the contrast control until the brightest patches stop merging into one white.
Check the grayscale and RGB steps
Both ends of the ramp should keep detail, and the red, green, and blue steps should stay separate.
What the result means
Match what you see to one of these.
If the dark patches merge, the black level is too low
If patches 1 to 4 all look the same black, the display or a range setting is crushing shadows. Raise brightness a little or fix the range.
If the bright patches merge, contrast is too high
If the lightest patches blend into one white, the contrast control, a range mismatch, or tone mapping is clipping highlights. Lower contrast one step at a time.
If one color loses steps before the others, that channel is clipping
If red steps merge while green and blue stay separate, a color setting or the panel is clipping that channel. A colorimeter is needed to correct it properly.
Troubleshooting
If the test fails, try these in order.
Match the range setting
Set both the graphics output and the display to full range, or both to limited. A mismatch crushes blacks or washes out the image. Look at the black level steps again.
Control the room light
A bright room hides dark patches. Judge black level at the light level you normally use, not by turning brightness up until every patch is obvious.
Turn off dynamic contrast and HDR
These change the levels while you watch. Turn them off and repeat both step patterns.
Check gamma next
Once the dark and bright steps stay separate, open the gamma test to check the midtones. Change only one control between checks.
What this test can't tell you
Where a browser check stops.
- The page cannot measure contrast ratio, black luminance, or peak brightness; it shows whether the steps stay separate on your settings.
- What you can see depends on room light, eyesight, browser color management, and the display, so use the same conditions each time.
FAQ
Common questions about this test.
What is a good contrast setting for a monitor?
The factory default, usually 50 to 75 on the display's scale, is right for most monitors. Contrast controls the white point, so lower it only if the brightest numbered patches merge, and use brightness for the black level.
Is higher or lower contrast better?
Neither on its own. Too high clips highlights and can tint whites; too low makes the picture flat. Set it to the highest value at which the white clipping steps stay separate.
How do I use the black level test?
In a dim room, adjust brightness until the first one or two dark patches are just visible. If every patch is easy to see, the black level is lifted and dark scenes will look gray.
Does this test measure my monitor's contrast ratio?
No. A contrast ratio needs measured luminance. This test shows whether your settings keep shadow and highlight detail.