Understanding your prescription

What your prescription really means

Ever wondered what all the symbols and numbers on your prescription mean?

'+' – Shows if you are long sighted (farsightedness) '-' – Shows if you are shorted sighted (nearsightedness)

PD – Pupillary distance is the distance between your eyes measured between your pupil centre points

Common layouts of prescriptions:

Below are examples of prescriptions. The first set are standard prescriptions. Look through these to get a feel. Typed prescriptions are generally quite easy to understand, it's mostly handwritten ones that cause problems. Doctors and opticians seem to go to the same handwriting school.

At the end of the page are examples of unusual cases you may encounter, with instructions for what to do. Skip straight to the more unusual items

This is a standard NHS prescription:
NHS standard prescription

It would be written as follows:
NHS standard prescription solution

Dolland & Aitchinson:

Dolland & Aitchinson example
  • This time the signs have been written ABOVE the numbers - they are still just standard +/- signs
  • Also, they optician has written 125 instead of 1.25. It should still be entered as '1.25' with a decimal point
  • There is only one value for Near ADD, this should be entered for both eyes

It would be written as follows: Dolland & Aitchinson solution


Specsavers example

It would be written as follows: Specsavers solution

Vision express

Vision Express example

Here the additions are placed away from the rest of the prescription, it would be written as follows: Vision Express solution

More unusual figures

Sometimes figures like this appear on your prescription. These are not needed to make your lenses.Figures not needed

Some prescriptions have this figure, which looks like a sideways 8. This means 'infinity'. And you should select 'infinity' from the list.

Infinity example

This prescription also has some figures scrawled underneath these are Additions for both intermediate and near distances. Even though it's a single figure, it applies to both eyes.Additions example

This would be written like this:
NOTE: Use the "My prescription is more complex than this..." link to show you this more advanced prescription area

Addition solution

Sometimes opticians write 'DS' in the CYL column. This simply means there is no astigmatism, and you can enter either nothing (leave the field blank) or select the phrase DS in the drop down.No astigmatism example