Learning how to read your contact lens prescription might be daunting at first. All contact lens prescriptions include a least three values: base curve, diameter, and power. However, for toric or multifocal lenses additional values will be added to the prescription, usually no more than four.

The specifications you can expect to see are as follows:

Base Curve (BC): The curvature of the lens in millimetres usually between 8.3 and 9.0.

Diameter (D): The diameter of the contact lens. This number ranges from between 13.8 to 14.5.

Power (PWR/SPH): Is a + or - figure followed by a number e.g. -4.50 or +0.25. This represents the level of visual correction needed, and whether your lenses correct long-sightedness (plus/+ powers) or short-sightedness (minus/- powers). For some contact lenses, the power may also be 0.00, plano or displayed with this symbol ∞ which is for non-prescription use e.g. coloured contact lenses.

If you have astigmatism or wear multifocal contact lenses you can read out full guide on how to read your contact lens prescription.

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