What contact lens details do I need to place an order?

While ordering contact lenses you will be asked to select certain parameters of the product that you are interested in. If you have a contact lens prescription from your eye doctor, you might see some of these parameters on it. We'll explain what each of them means below:

  • OD - Right Eye
  • OS - Left Eye
  • Brand Name (e.g. Acuvue)
  • BC / Base Curve (a number between 8.0 and 10.0) - the "roundness" of the lens (the higher the number, the flatter the lens)
  • DIA / Diameter (a number between 13.0 and 22.0) - diameter of the lens (the higher the number, the wider the lens)
  • SPH Power / SPH / Sphere / Rx (a number between -20 and +20) - corrective power of the lens

For astigmatic patients, you will also need to provide:

  • CYL Power / CYL / Cylinder (a number between -4.00 and +4.00) - lens power for astigmatism, can be minus (for nearsighted astigmatism) or plus (for farsighted astigmatism)
  • Axis (a number between 0 and 180) - the lens meridian that does not contain a cylinder power, used to correct astigmatism

    CYL Power / Cylinder and Axis are usually separated by "X" and read as "times"

For presbyopic patients, you will also need to provide:

  • ADD (a number between 0.75 and 3.00, with or without "+") - an added plus power at the bottom of the multifocal or bifocal lens
  • While ordering CooperVision multifocal lenses: Dominance (D or N) - Eye Dominance and Non-Dominance. Dominant eyes are prescribed lenses with distant-centered design and non-dominant eyes with near-centered design.