What is a Landolt C?
The Landolt C is a ring with a gap. In a controlled test, the ring becomes progressively smaller and the viewer identifies the direction of the opening. Because the task uses orientation rather than alphabet letters, it can reduce some language and literacy barriers.
Try the screen demonstration
This interactive example is for learning only. Monitor size, resolution, viewing distance, brightness and browser scaling are not calibrated, so the result is not a measure of your clinical visual acuity.
Which way does the gap face?
C
Choose a direction to begin.
Safety note: This demonstration is not a diagnosis. Sudden blur, vision loss, pain, flashes, many new floaters or a shadow in vision require prompt professional assessment.