Use our online strength calculator to find your ideal strength in reading glasses and sun readers from your prescription:
The prescription used should be from within the last two years.
Please note, this calculator provides an accurate guide to your reading strength and does not replace regular eye tests and consultation with your optician.
• Enter the values for sphere
and near add
from the drop down menus, as they appear on your prescription for each eye. The axis value on your prescription can be ignored and is not required for this calculation.
• Make a decision as to what the reading glasses are required for
, either for reading
(near or close work such as reading a book, sewing or using a phone or tablet) or for using a desktop or laptop computer
• Also select which is your dominant eye
. This would be the eye that you would use to aim. If you are unsure you can point at a distance object with both eyes open and then close one eye at a time. The eye which is pointing directly at the object
should be your dominant eye, the other will be off to the side.
Please feel free to contact us
should you need any further help.
Should you not have a prescription available, your optician
will also be able to tell you your ideal strength reading glasses either if they have your current glasses prescription on file or at the completion of an eye test.
Alternatively, as a good approximate guide to your reading strength please download and print out our eye chart
which is in PDF format:
Download Eye Chart