What is the normal focal length for a camera lens?

The normal focal length for a camera lens is typically considered to be around 50 mm when using a full-frame camera with a 35 mm film equivalent sensor. This focal length closely approximates the field of view and perspective that the human eye experiences, making it ideal for capturing images that appear natural to viewers. The 50 mm lens provides a balance between wide-angle and telephoto capabilities, enabling versatile shooting options for a variety of subjects. It is often referred to as a "standard lens" because it offers a realistic portrayal of scenes without significant distortion.

While other focal lengths like 24 mm, 35 mm, and 100 mm are commonly used in photography, they serve different purposes. For instance, a 24 mm lens is typically used for wide-angle shots, making it great for landscapes or interiors, whereas a 100 mm lens is often favored for macro photography or portraits, as it allows for tighter framing and subject isolation. However, the 50 mm focal length remains the benchmark for what is considered a normal perspective in photographic composition.