Crop Factor Calculator
Convert focal length and aperture to their full-frame equivalents.
About this tool
A crop factor calculator that converts a lens's focal length and aperture into their 35mm full-frame equivalents. Choose a sensor (or enter a custom factor) and optionally a focal length and f-number to see the equivalent field of view and the depth-of-field equivalent aperture, with a clear note that exposure is unchanged. Includes a crop-factor reference table.
Frequently asked questions
How do I find the equivalent focal length?
Multiply your lens focal length by the sensor crop factor. A 35 mm lens on an APS-C body (1.5×) frames like a 52.5 mm lens on full-frame.
Does the crop factor change my f-number for exposure?
No. The f/1.8 you set stays f/1.8 for exposure — shutter and ISO are unaffected. The equivalent aperture only describes depth of field and total light gathered relative to full-frame.
What are the standard crop factors?
Full-frame 1.0×, APS-C 1.5×, Canon APS-C 1.6×, Micro Four Thirds 2.0× and 1-inch 2.7×.
Can I enter a custom crop factor?
Yes, use factor=1.5 instead of a named sensor for any body whose multiplier you already know.