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Visual Acuity - what does it mean?

Visual acuity describes how well you can see high contrast detail in the centre of your vision.

Resolution visual acuity

• Acuity can be estimated from infants and those with communication difficulties using special techniques that measure resolution acuity more

Recognition visual acuity

• Recognition visual acuity is the type of acuity measured from someone who is able to match or name pictures or letters more

How is visual acuity recorded?

• Visual acuity is usually recorded as a Snellen fraction such as 6/60 (UK) or 20/200 (US) more

Snellen fraction conversions

• Other ways of recording acuity e.g. cycles per degree and LogMAR may be converted to Snellen fractions more

If you have a recorded visual acuity (e.g. 6/60 or 20/200) these web pages should allow you to obtain a print out of the size of images that you should be able to see easily at different distances.

A person’s visual acuity reflects only one aspect of their vision. There are many other aspects of vision such as refractive error, accomodation, contrast sensitivity, cognitive visual function, visual fields and eye movements which will all impact on how well a person sees and uses their vision.