What does 30/20 vision mean?

I just got an eye exam and the doctor said I have 30/20 vision and a little bit of astigmatism in my left eye, what does this mean because the doctor really didn't explain it.

30/20 vision means that you can read a letter at 30 feet that a person with "normal" vision would have to come up to 20 feet to read. Therefore your vision is better than a "normal" person's. (My vision is 20/100, which means that I have to come up to 20 feet to read a letter than everyone else can read at 100 feet!)

Astigmatism is an uneven curvature of the lens or the cornea of your eye. Almost everyone has some degree of astigmatism. Read more about it at http://www.mayoclinic.com/health/astigma...

Your vision is probably better than most people's!

umm thats good vision then. GREAT JOB!

Sure he didn't mean 20/30? 30/20 would mean that someone with "average" vision would see something just as well from 20 feet away as you if you were 30 feet away. For a more extreme example, 20/100 would mean you would have just as much trouble seeing something 20 feet away as someone with normal vision would if they were 100 feet away. So 30/20 means you're better than average. An astigmatism is very common, it means your eye is starting to take the shape more of a football than a sphere, and it just means you'll have trouble with contact lenses.

Are you sure it wasn't 20/30? 30/20 is not a standard way of recording visual acuity. The top number specifies the distance from the chart and the bottom number specifies the smallest size of letter you could see. 20/20 is considered normal, 20/30 is slightly worse.

The "30" size subtends 5 degrees of arc in total size and the critical detail subtends 1 degree of arc if viewed from 30ft away, it would be a letter about 1" tall. The "20" size letter subtends the same arc if viewed from 20 ft away, it is a letter about 3/4" tall.

If 20/30 is your vision, it means you have slightly blurred vision and would see slightly better with glasses.