Skip to main content

Eyeglass prescription explained


How can I tell what my vision problem is ?

This is quite simple to do by looking at your distance eyeglass prescription.

Sample Prescription


  • Your eyeglass prescription has a main number called the “sphere”.

  • If your sphere has a + sign, you are far-sighted or hyperopic.

  • If your sphere has a - sign, you are short-sighted or myopic.

  • If you have any astigmatism, the prescription will then have 2 more numbers:
    the “cylinder” is the amount of astigmatism, and the “axis” describes its orientation.

  • Your prescription may also have a last number called the “add”.
    This is the amount of bifocal you require to compensate for presbyopia.

  • The sphere, the cylinder and the add are measured in units called “diopters”.
    The axis is measured in degrees.