The Uk's Online Lens Experts

Your prescription explained

Understanding your sight test prescription


Before you even contemplate buying your glasses online you will need an up-to-date sight test, that must not be more than 2 years old if you are aged between 16 to 70, or no more than 1 year old if you are over the age of 70. Your sight test prescription is the most important piece of information when it comes to purchasing your online glasses. This is because your sight test prescription specifies every detail in order for us to make your prescription glasses in accordance with your eye examination results. If you are unfamiliar with what your sight test prescription should look like, then take a look at the picture below.

The first line on your sight test prescription card will generally be for your distance prescription. The value under SPH power is for your spherical power and will either have a plus or minus sign before it. This number indicates the initial strength of the prescription needed to correct your vision (both distance and near).




If the optician has specified a CYL and AXIS number on your sight test prescription then the reason for this is that you have what we call an astigmatism. This occurs when the front surface of the eye (the Cornea) is not perfectly spherical. This causes light to bend as it enters your eye and thus your eye cannot focus the light properly on the back of the eye or the retina.

If you have an astigmatism then there will also be a value listed under CYL with either a minus or plus sign before it as well. Anyone who has an astigmatism will always have a number under AXIS that will be anything from 1 to 180.


If you require reading glasses then there may be another value listed underneath your distance prescription which may read something like 'ADD +2.50'. This tells us that in order to work out your reading prescription, we need to add a value of 2.50 to your distance prescription.

PLEASE NOTE: Some opticians will write your reading prescription out in full, separately, under where your distance prescription is specified.

If you have any problems with entering your prescription details when ordering your online glasses then call us on 01252 721735 and one of our qualified dispensers will be happy to help you complete your order to ensure that your online glasses are made to correct specifications.

We can supply bifocal glasses and varifocal glasses if you require both reading and distance prescriptions. Our team of experienced dispensers and technicians will ensure that when you receive your new prescription glasses, you will experience maximum visual acuity through your premium lenses. Don't forget that if you wish to order varifocal glasses or bifocal glasses then simply email us with your contact details and one of our staff will call you back within the hour to verify the details that we require.