Optometrists generally agree on a sort of baseline for reading glasses. People who are ages 40 to 44 will generally need reading glasses at a strength of +1.00 diopters.
Individuals age 45 to 49 will generally need reading glasses that have a strength of +1.50 diopters. Age 50 to 54 will need reading glasses that have a strength of +2.00 diopters. Age 55 to 60 will need reading glasses that have a strength of +2.50 diopters.h Strength Reading Glasses You Need