If you are currently wearing frames and have not yet used contact lenses, it is recommended that you make the following conversions, no action is required for prescriptions less than -4.00, the following are only for prescriptions above -4.00.

Contact Lenses Prescription Conversion

-4.00 ~ -7.50 -7.75 ~ -11.25
Frame Glasses Contact Lenses Frame Glasses Contact Lenses
-4.00 -3.75 -7.75 -7.00
-4.25 -4.00 -8.00 -7.25
-4.50 -4.25 -8.25 -7.50
-4.75 -4.50 -8.50 -7.75
-5.00 -4.75 -8.75 -7.75
-5.25 -5.00 -9.00 -8.00
-5.50 -5.00 -9.25 -8.25
-5.75 -5.25 -9.50 -8.50
-6.00 -5.50 -9.75 -8.75
-6.25 -5.75 -10.00 -8.75
-6.50 -6.00 -10.25 -9.00
-6.75 -6.25 -10.50 -9.25
-7.00 -6.50 -10.75 -9.50
-7.25 -6.50 -11.00 -9.75
-7.50 -6.75 -11.25 -9.75
Note 1:  If you have a slight astigmatism (astigmatism less than -1.50, and the ratio of myopia and astigmatism is greater than 4), you can add one-half of the astigmatism in the optometry, and then convert the corresponding contact lens prescription. (Example 1: myopia-4.50 astigmatism-0.75 converted to -4.50 degrees; Example 2: myopia-4.50 astigmatism-1.00 converted to -4.75 degrees)
Note 2:  If you do not have myopia, please select “PLANO”.
Note 3:  If there is no corresponding degree for a certain myopia, you can choose the degree that is closest to the lower one (e.g. -8.00 degrees reduced by 75 degrees is -7.25 degrees, if there is no -7.25 degrees, you should choose -7.00 degrees, and so on).