How to conduct an eye exam with a Snellen Chart

Updated February 21, 2017

If you want to test your eyesight, a Snellen Chart is the easiest and most accurate way to do it. This is the same chart optometrists use to determine your ocular acuity. Conducting this eye exam at home is a fun and simple way to make sure your vision is at its best.

Attach the Snellen Chart to a wall at eye-level.

Measure 6 metres (20 feet) from the chart using the measuring tape. Mark this distance with a piece of tape on the floor to use as a reference point.

Stand at the twenty feet mark and read the lines of the Snellen Chart from top to bottom. Note the final line that you are able to read completely and with ease. Approach the chart and note the number next to that line of letters; this number will be your visual acuity. If this number is 6/6, you have normal vision. If the number is 6/12, your vision is approximately half as good as a normal person's vision. Those numbers mean that what a normal person can read from 12 metres away, you can only read from 6 metres.

Talk to your optometrist about receiving glasses or contact lenses if your eye exam result is a number in which the second integer is higher than 6; you likely need corrective eye wear.


If you already wear corrective lenses, wear your lenses during your eye exam.

Things You'll Need

  • Snellen eye chart
  • Measuring tape
  • Masking tape
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About the Author

Ellis Martin recently graduated from Brown University, where he wrote for the Brown Daily Herald. Martin has many articles published on eHow, mostly concerning medical topics. He has been writing these articles since the summer of 2009.