Reading Glasses and Contact Lens Prescriptions
Over 10 years of working with our visitors to ensure their eye health needs are met has helped our Vision Ambassadors to define some of the top questions that we’ve received. The top question by far is: what are the numbers on my glasses and contact lens prescriptions and how do I read them? Our Head Optician, Claudia Rojas took the time to walk through the training that she’s provided to our Vision Care Team.
The following are some tips on understanding your eyewear prescriptions. If you’re unsure of anything call our Vision Care team at 1-866-333-6888 who are also happy to contact your Eye Care Provider to check your prescription on your behalf.
What do the numbers on my prescription mean?
Your prescription may include a SPH, CYL, Axis, ADD and Pupillary Distance (PD). If your prescription does not include one of those it simply means that you do not require that corrective power. There is a separate prescription for your right eye, and for your left eye.
Right eye parameters
Left eye parameters
Sphere indicates the amount of lens power prescribed for nearsightedness or farsightedness.
CYL & AXIS
A Cylinder (CYL) and Axis is required to correct Astigmatism. Both parameters will be required together.
This provides magnifying power for reading, progressive and bifocal lenses. You will have the same number for both eyes.
How do I Read My Glasses Prescription?
In addition to the general parameters, a glasses prescription also requires a Pupillary Distance (PD).
Pupillary Distance (PD)
PD is the distance between the centre of one pupil (the central black dot of your eye) to the centre of the other pupil, measured in millimeters.
This is how you would include the numbers on our website for glasses:
How do I Read My Contact Lens Prescription?
In addition to the general parameters, a contact lens prescription will include a Base Curve and a Diameter.
BASE CURVE (BC) & DIAMETER (DIA)
Both the Base Curve (BC) and Diameter (DIA) of a contact lens ensures a proper fit on your cornea and total eye surface to ensure comfort, and encourages eye health including allowing proper oxygen to the eye.
This is how you would find your prescribed contact lens product and enter your prescription:
1) Find your prescribed brand (in this case it is Acuvue 2 but your Eye Care Professional will prescribe the best product for your eye health)
2) Following your prescription, enter the Power, Base Curve and Diameter
If you have any questions about your glasses or contact lens prescription call our Vision Care Team at 1-866-333-6888 for assistance.
Have a valid prescription and ready to shop?