CalKit

Vision Calculator

Convert diopter to visual acuity.

D
D
종합 시력 판정
경도
경도

우안 (오른쪽)

디옵터-2.00 D
시력 (근사치)20/70
판정경도
유형근시

좌안 (왼쪽)

디옵터-1.50 D
시력 (근사치)20/58
판정경도
유형근시

추가 정보

좌우 차이0.50 D
부등시 (좌우 차이 2D 이상)해당 없음

Overview

The Vision Converter Calculator converts between diopter (D) values, decimal visual acuity, and Snellen fractions. It helps you understand eyeglass or contact lens prescriptions and assess your vision status.

Formula

Decimal acuity ≈ 1 / (1 - 0.4 × diopter) (approximation for mild myopia) | Snellen conversion: 1.0 = 20/20, 0.5 = 20/40, 0.1 = 20/200 | Diopter: minus (-) = myopia, plus (+) = hyperopia | Example: -2.00D → decimal ≈ 0.3-0.4, Snellen ≈ 20/60

How to Use

  1. 1Enter a diopter value or decimal visual acuity.
  2. 2Select the target notation system for conversion.
  3. 3Click 'Calculate'.
  4. 4Review the converted values across diopter, decimal, and Snellen systems.

Tips

  • ✔The relationship between diopters and visual acuity is approximate, not mathematically exact.
  • ✔Actual vision can vary even at the same diopter due to astigmatism, corneal conditions, etc.
  • ✔Eyeglass and contact lens prescriptions may differ due to vertex distance.
  • ✔For accurate vision testing, consult an ophthalmologist or optometrist.

FAQ

Q. Does a higher diopter mean worse vision?

Yes. A larger absolute diopter value indicates greater refractive error and generally lower uncorrected acuity. -6.00D or beyond is classified as high myopia.

Q. Is 20/20 (1.0) perfect vision?

20/20 (decimal 1.0) is the 'normal baseline' — not the maximum. Some people have 20/10 (2.0) or better acuity. It is a reference point, not an upper limit.

Q. Why are my glasses and contact lens prescriptions different?

Glasses sit about 12 mm from the eye, while contacts rest directly on the cornea. This vertex distance difference requires prescription adjustment, especially above -4.00D.

Related Calculators

BMI Calculator

Check your body mass index (BMI) and weight status.

BMR Calculator

Calculate your basal metabolic rate and daily calorie needs.

Water Intake Calculator

Calculate daily recommended water intake based on weight and activity.

Body Fat Calculator

Estimate body fat percentage using the US Navy method.

Ideal Weight Calculator

Calculate ideal weight range based on height and gender.

Target Heart Rate Calculator

Calculate target heart rate zones by exercise intensity.