Created By : Naaz Fatima

Reviewed By : Phani Ponnapalli

Last Updated : May 18, 2023

The The Aperture Area Calculator will determine the aperture area of a lens in a matter of seconds. All you have to do is enter the required information and press the calculate button to get instant results.

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Focal length:

Aperture Diameter and f-number

An aperture is a hole or opening in an optical system that allows light to pass through. The bigger the aperture, the more light comes in and the light is collimated less. The diameter of the opening is known as the aperture diameter.

The f-number and focal length are two further parameters of an optical system. The focal length is just the distance that collimated rays are brought to a point of focus. The longer the focus length, the more clearly distant things can be seen. The f-number, on the other hand, is the ratio of the focal length f to the aperture diameter D, i.e. n=f/D.

We can set the f-number to predefined numbers in commercial lenses, such as 1.4, 2, 2.8, 4, 5.6, and so on. They show a √2 times reduction in aperture diameter and a 2 factor reduction in aperture area.

Area of Aperture Formula

The following are two different ways to describe Aperture Area: A = π (D / 2)2= π (f /(2 * n))2

  • Here, D be the Aperture Diameter
  • f be the focal length
  • n be the f-number
  • A be the Aperture Area


For more concepts check out physicscalculatorpro.com to get quick answers by using this free tool.

Area of Aperture Examples

Question 1: Find the Area of the Aperture If the f-number is 1.3 and the focal length is 12 mm?


we have the inputs,

Focal length = 12mm


We know the formula to find the Area of Aperture using f-number is A = π (f / (2 * n))2

Substituting the input parameters in the above formula we have the equation as such

Aperture diameter A = π(12 / (2 * 1.3))2.

A = π(12/(2.6))2

A = π(4.62)2

Aperture diameter A=3.14(21.3)

Therefore, Area of Aperture diameter=66.9mm2

FAQs on Aperture Area Calculator

1. How do I calculate the Aperture Area?

The Area of Aperture can be calculated by multiplying pi by half of the aperture diameter squared.

2. What is the Area of Aperture Formula?

The Area of Aperture Formula is A = π (D / 2)2

  • Here, D be the Aperture Diameter
  • f be the focal length
  • n be the f-number
  • A be the Aperture Area


3. In the Aperture Area Formula, what is f?

In the Aperture Area Formula, f stands for focal length.