Tools / Vertex distance
Vertex Distance Calculator
Convert spectacle power to ocular power at a chosen vertex distance.
Last updated: March 2026
Formula
F' = F / (1 − d × F)
Exact ocular power: -4.72 D
Rounded to 0.25 D: -4.75 D
Tools / Vertex distance
Convert spectacle power to ocular power at a chosen vertex distance.
Last updated: March 2026
Formula
F' = F / (1 − d × F)
Exact ocular power: -4.72 D
Rounded to 0.25 D: -4.75 D