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Vision Test


Before you call your doctor to schedule an eye exam, there is actually something you can do right now. It’s called the Diopter test.  This test will help you see if you need readers and if you do, which ones.

Download Reading Test 

Print the paper and follow the instructions.

Hold the paper 16-18 inches from your face. Start to read the line with the lowest number (+1.00). Continue to read the line above until the words become clear. Then look to the left and see your diopter measurement.



There are a few tricks you should know to make sure you get the most out of your reading glasses.

Normal reading of a book or your phone is done about 18 inches from your face. If you find yourself needing to do something closer to your face, like doing detailed model work, then you'll want to increase your diopter number. How close it is to your face will depend on how much of an increase you need.

If your number is +2.00 when you read at a normal distance (18 inches), jump to +3.00 if you need to read something in four to ten inches from your face. If it’s eight to twelve inches your increase would be by +.50, bringing you up from +2.00 to +2.50.

If you spend quite a bit of time on a computer, you’ll want to do the opposite. The farther away the monitor the more you’ll lower the power.

If your monitor is 30 to 36 inches away, then you’ll want to decrease your power by .25. If your number is +2.00, then you’ll want to grab a pair of glasses at +1.75. If you need to read something 36 to 48 inches away, drop the power by .50, bringing our example to +1.50.

As a rule, you should increase your diopter number the closer you move something to your face, and decrease your number as the object moves farther away. If you need to read anything past four feet, reading glasses will not have much of an affect.

The more you increase your number, the closer your focal point. As you decrease your number, your focal point moves farther away.

Here’s a chart that breaks it all down.


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