Lens Focal Length Crop Factor Calculator
Calculate equivalent focal length, field of view, and depth of field changes across different sensor sizes
About this calculator
The Lens Focal Length Crop Factor Calculator helps photographers understand how different sensor sizes affect their lens performance. When using the same lens on cameras with different sensor sizes, the effective field of view changes due to crop factor multiplication. This calculator instantly computes the equivalent focal length, field of view changes, and depth of field variations across various sensor formats including full-frame, APS-C, Micro Four Thirds, and others, making lens selection and composition planning effortless.
How to use
Enter your lens's actual focal length and select your camera's sensor size from the dropdown menu. The calculator will automatically compute the equivalent full-frame focal length by applying the appropriate crop factor. Compare results across different sensor formats to understand how the same lens performs on various camera bodies.
Frequently asked questions
What is crop factor and why does it matter?
Crop factor is the ratio between a full-frame sensor and smaller sensors. It affects field of view, making lenses appear more telephoto on smaller sensors.
Does crop factor affect the actual focal length of my lens?
No, crop factor doesn't change the lens's physical focal length, only the effective field of view and angle of coverage on different sensor sizes.
How does sensor size impact depth of field?
Smaller sensors generally provide greater depth of field at equivalent focal lengths, while larger sensors offer shallower depth of field for better subject isolation.