Prescriptions

Your PD,
in two minutes.

PD, your pupillary distance, is the distance between the centres of your pupils in millimetres. It tells the lab exactly where to put the centre of each lens. Most adults measure between 54 and 74. There are three ways to get yours; the first is the easiest.

The easiest

Ask your optician

The practice that tested your eyes measured your PD. It is often not printed on a UK prescription, but they will usually give it to you if you ring or email and ask for it.

On your own

A mirror and a ruler

  1. Stand about 20 cm from a mirror in good light, holding a millimetre ruler flat against your brow, just above your eyes.
  2. Close your right eye. Line the ruler’s zero up with the centre of your left pupil.
  3. Close your left eye and open your right. Read the number at the centre of your right pupil. That is your PD.
  4. Do it three times and use the number that comes up most often.

With a friend

Someone else reads it

  1. Sit facing them at arm’s length, in good light.
  2. Look past them at something at least three metres away, and keep looking at it.
  3. They hold a millimetre ruler just under your eyes, line zero up with the centre of one pupil, and read the number at the centre of the other.
  4. Twice more, and take the number that repeats.

Then send it to the house

Reply to your commission email with the number, or write to hello@paulsagoo.com with your reference. If you have two numbers, one for each eye (for example 31.5 and 32), send both.

Bifocals and varifocals also need fitting heights. Do not measure those yourself: the house takes them from a photograph of you wearing the frame, and writes to you to arrange it.

Not sure you got it right? Send what you have. A person checks every figure before a lens is cut, and will measure it with you from a photograph if needed.