How to read your glasses prescription

OD = oculus dexter = right eye.

OS = oculus sinister = left eye.

Some doctors write RE / LE instead. The order on the form is almost always right eye first.

The main strength of the lens, in dioptres. Negative values (for example -2.25) correct nearsightedness — you see close up but not far away. Positive values (for example +1.50) correct farsightedness or are used for reading glasses. A value of 0.00 means that eye does not need correction.

The amount of astigmatism correction needed, in dioptres. May be left blank, written as 0.00, or written as DS / SPH meaning no astigmatism. If CYL has a value, Axis must also have a value.

A whole number between 1 and 180. It tells the lab the orientation of the astigmatism correction. It only matters when CYL is non-zero, and a small mistake here causes very noticeable blur — copy this number carefully.

The additional reading power for bifocal, progressive, or reading-only prescriptions. Always a positive number, typically +0.75 to +3.00, and usually the same for both eyes. If your prescription has an ADD value and you are buying single-vision distance glasses, you do not enter ADD here.

A correction for eye-alignment issues. Written as a decimal (for example 1.5) plus a direction (BU base up, BD base down, BI base in, BO base out). Prism prescriptions need extra review on our side — please upload the prescription form and our team will contact you before cutting lenses.

Pupillary distance, in millimetres. See the dedicated PD measurement guide.

Single vision. One SPH per eye (and CYL/Axis if you have astigmatism). No ADD. Choose single vision in the lens flow.

Reading only. A positive SPH or just an ADD value. Choose reading in the lens flow.

Non-prescription. No prescription at all — you just want the frame, optionally with blue-light or tint. Choose non-prescription.

Not sure. Upload a photo of your prescription form and we will read it for you. This is the safest option if anything on the form is unclear.

An incorrect SPH, CYL or Axis means a pair of lenses you cannot see through. Contact support or use the upload-prescription option. We would rather review than re-make.