Click the tile that's slightly different from the rest. The difference shrinks each level.
Why it matters
Contrast sensitivity is a different skill from visual acuity — it determines how well you can tell an object apart from its background under poor conditions, like dusk, fog, or glare. This ability tends to decline with age and fatigue before classic visual sharpness does.
Sensitivity to subtle contrast differences — the ability to distinguish an object from its background even with a very small brightness gap.
Drivers and athletes who need to spot details in poor lighting conditions, and anyone wanting to test the quality of their visual perception.
Rating scale
The test is inspired by clinical contrast sensitivity tools (e.g. the Pelli-Robson chart), used in optometry alongside standard visual acuity tests. Your screen's brightness and settings significantly affect the result — treat it as a rough indicator rather than a precise clinical measurement.