What do the numbers in a binocular name mean?

The numbers describe the configuration of a binocular. Let's take 8x42 binoculars as an example. The first number (8) refers to the magnification, or, how many times closer an object will appear when looking through the binocular compared to looking through eyes only. The second number (42) indicates the diameter of the objective lens (the light-gathering lens) of the binocular and is measured in millimeters.

Note: The diameter of the objective lens is directly related to the size of the binocular -- the larger the objective lens, the larger (and often brighter) the binocular.

List of common binocular questions.




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