Follow Us On:

Your Result is copied!

Magnification Calculator

Add the focal length and the distance of your subject to calculate the Magnification through this calculator.

centimeters (cm)

milimeters (mm)

meters (m)

kilometers (km)

inches (in)

yards (yd)

miles (mi)

centimeters (cm)

milimeters (mm)

meters (m)

kilometers (km)

inches (in)

yards (yd)

miles (mi)

Add this calculator to your site


The magnification calculator allows you to calculate the magnification by just adding the distance of the object from the lens and the distance upon which the image is formed from the lens.

Just add the values and get the result instantly.

Magnification Definition:

It is the process of lens refraction that reflects an image onto the surface and is referred to as the ratio of the distance from the image to the actual distance of the object.

In simple words, this is the process of making something look bigger and closer to the eyes. For instance, if you use a magnifying glass to look at the leaf then it zooms the leaf and lets you have a closer look at the details of the leaf.

Magnification Formula:

The main ability of a telescope is that it makes it possible to see distant objects clearly. The magnification power of a telescope is observed by the focal length of the telescope and the focal length of the eye’s piece.

Let's take a look at the following equation for calculating magnification:

The formula for Magnification = M = Telescope Focal Length / Eyepiece Focal Length

M = H / G

M = (d / 2 - r) / (d / 2 + r)

Here “r” represents the square root of the following equation:

r = SQRT( ((d)^2 / 4) x (f x d))


  • M represents magnification.
  • H shows the formed image distance from the lens.
  • G is the actual distance of the object from the lens.

Whenever you are taking a photo, you will probably not know the values of h and g. But you will surely know the focal length and the distance between you and the body or object. If you know both of these values then you can easily find out the magnification of the lens correctly.

Instead of using the above-mentioned magnification formula, just add these two values in the designated field of our online magnification calculator and get the results instantly. It saves you from performing long calculations.

How Do You Calculate Magnification?

Go through the following steps to get the magnification:

  • First you need to calculate the object distance from the lens using a distance measuring device.
  • After that determine the formed image distance from the lens.
  • Now add the values in the above-mentioned equation for magnification.

Keep in mind that each telescope has a magnification limit. If you start going beyond that limit then instead of becoming clear, the image starts to become blurred. Meanwhile, you will start facing blurriness and optical aberrations.

Working of an Online Magnification Calculator:

Our online calculator requires you to provide a couple of inputs to get accurate results instantly. Let's take a look!


  • Add the values of “Focus distance” and “Focal distance” in the designated fields.
  • From the drop-down menu, select the appropriate measurement units.
  • Now, tap on the “calculate” button to proceed with the calculation.


  • Correct magnification.
  • Object & Sensor Distance.


Can Magnification be Zero?

When the magnification is greater than one, it means an enlarged image will be shown but if the value of the magnification is lower than one then it shows a diminished image. When it's completely zero then it means no image is formed.

Is Magnification always 1?

When the size of the formed image is equal to the size of the actual size of the object then the magnification is 1.

What Magnification is Legally Blind?

Vision less than 20 / 200 is typically considered legally blind.

Does Magnification Increase with Focal Length?

Longer focal length means more narrow-angle of view and high magnification. On the other hand, the smaller focal length means a wide angle of view and low magnification.

What Does Magnification +2 mean?

Whenever you see magnification +2 then it means the case of an enlarged image. The image that Is formed by the convex lens is erect and virtual and is larger than the actual body or object.


From the source of Introduction to Magnification, What is Magnification? – Definition.

From the source of Wikipedia: Magnification

Online Calculator



Get the ease of calculating anything from the source of calculator online

© Copyrights 2024 by