What is the difference between Diopter and magnification?


Diopter refers to the curvature of the lens. As the diopter increases, the lens become thicker and the curvature greater. As the curvature increases, light rays are redirected to fill a greater portion of the viewer’s retina which makes the object look bigger.

Powers refers to how much larger an object is made to look through a magnifying lens. Power is typically indicated by an X such 2X or 4X.

There is more than one formula to converts the diopter of a lens into its power, we as a company use the common formula: Magnification = (Diopter / 4) +1

For example an 3 diopter lens makes an object look 75% times larger, over and above what the unaided eye already sees.

Common diopter/power

Diopter Power %Bigger
3 1.75 75%
5 2.25 125%
7 2.75 175%
8 3.00 200%
11 3.75 275%
12 4.00 300%
15 4.75 375%