PLEASE NOTE: Not intended for multifocal contact lenses
If you have a prescription for glasses and are looking to buy some contacts this conversion calculator is for you. Although we recommend seeing your eye care professional for an expert contact lens fitting and prescription, our calculator will allow you to convert your glasses prescription to a contact lens prescription. All you have to do is plug in your prescription values and press the calculate button. Follow these easy steps!
Step 0: Begin with the prescription for your right eye. The right eye is usually written as O.D. meaning Oculus Dexter and is placed just above the O.S.
Step 1: Enter your sphere number into the sphere tab. Sphere is usually written as SPH. Make sure to include the + symbol in front of this value if plus or the – symbol if minus.
Step 2: If you have a cylinder value, enter it into the cylinder tab. Cylinder is usually written as CYL. Make sure to place the – symbol in front of the cylinder value. If you’re cylinder has a plus cylinder, it needs to be converted to the minus form. Click HERE to convert your prescription to the minus form before proceeding.
Step 3: If you have a cylinder value, you will also have an axis value. Axis is usually written as AXIS. Enter your axis value into the axis tab.
Step 4: Repeat Steps 1 – 3 for your left eye. The left eye is usually written as O.S. meaning Oculus Sinister and is placed just below the O.D.
Step 5: Click the calculate button! Write down your converted prescription.
Now you are ready to shop for contacts!