Glasses to Contacts Prescription

Convert your eyeglasses prescription to contact lens values using vertex distance adjustment. Accounts for sphere and cylinder power changes at different distances.

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How to Use

  1. Enter your glasses prescription (sphere, cylinder, axis for each eye).
  2. Optionally adjust the vertex distance (default 12mm).
  3. View your estimated contact lens prescription.

Frequently Asked Questions

Why are glasses and contact lens prescriptions different?

Contact lenses sit directly on your eye, while glasses sit about 12mm away (vertex distance). This distance affects the effective power of the lens, especially for prescriptions above +/-4.00 diopters.

Is this converter accurate enough to order contacts?

This tool provides a good estimate, but you should always have your contact lens prescription verified by an eye care professional before ordering.

What is vertex distance?

Vertex distance is the distance from the back of a glasses lens to the front of your eye, typically about 12mm. It affects the effective power of the correction.

Does it handle astigmatism?

Yes. The converter adjusts both sphere and cylinder values for prescriptions with astigmatism.

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