Use this handy crop factor calculator to work out the 35mm full frame equivalent focal length of any crop sensor camera.
The crop sensor cameras included in this calculator are:
- Canon APS-C
- Nikon APS-C
- Sony APS-C
- Fuji APS-C
- Pentax APS-C
- Panasonic / Olympus Micro Four Thirds
Crop Sensor to Full Frame Calculator 📸
This crop factor calculator will let you see what a lens will look like on your camera if the lens was on a 35mm full-frame sensor camera instead of a crop sensor camera.
Why Does 35mm Equivalent Focal Length Matter?
Knowing the full frame equivalent focal length of your lens and camera combo can be very important.
Here’s why.
If you are listening to lens recommendations from another photographer and they are using a full-frame sensor then if they say that an 80mm lens is perfect for a specific purpose, then they mean 80mm.
But if someone else is using a Canon APS-C sensor camera they might say that a 50mm lens is perfect for that same purpose instead.
This is because the crop factor on a Canon APS-C camera is about 1.6x which means that a 50mm lens actually looks more like 80mm if it were on a full-frame sensor.
Always pay attention when someone is recommending lenses to you. This way you’ll know whether they are talking about the full frame equivalent focal length or just the focal length of the lens without a crop factor applied.
How is Crop Factor Calculated?
The crop factor is calculated by comparing the diagonal length of a crop sensor to the diagonal length of a 35mm full-frame sensor.
So a Canon APS-C sensor has a diagonal length that is 1.62x smaller than a 35mm full-frame sensor.
Similarly, APS-C cameras from Nikon, Sony, Fuji and Pentax have a diagonal length that is 1.53x smaller than a 35mm full-frame sensor.
Micro four thirds sensors from the likes of Olympus and Panasonic have a diagonal length which are 2.0x smaller than a 35mm full-frame sensor.
Focal Length Conversion
You can use the crop factor of a sensor to do a focal length conversion from APS-C to full frame and vice versa.
To do a conversion from APS-C focal length to its 35mm full frame equivalent focal length, you take the focal length of the lens and multiply it by the crop factor of the sensor.
💡 e.g. If using a 50mm lens on a Canon APS-C camera…
- Focal length of lens = 50mm
- Canon APS-C sensor crop factor = 1.62x
- Full frame equivalent focal length = 1.62 x 50mm = 81mm
This is useful because if someone says a 50mm lens looks amazing for portraits on an APS-C sensor you can figure out what it would take to get the same look on a full-frame sensor.
In this example, you would get an 81mm lens for your full-frame sensor camera to replicate the look of a 50mm on a Canon APS-C camera.
You can also do the opposite…
To do a focal length conversion from a full frame equivalent to an APS-C focal length, you take the focal length of the lens and divide it by the crop factor on the APS-C sensor you want to compare to.
💡 e.g. If using a 50mm lens on a full-frame camera and you want to compare it to a Canon APS-C camera
- Focal length of lens = 50mm
- Canon APS-C sensor crop factor = 1.62x
- APS-C equivalent focal length = 50mm / 1.62x = 31mm
This is useful if someone says a 50mm lens on a full-frame camera looks amazing for street photography and you want to figure out how to get the same look using your APS-C sensor camera.
In this example, you’d look for a 31mm lens for your APS-C Canon camera to replicate the look of a 50mm lens on a full-frame camera.
Related Reading:
Find out more about the differences between crop sensor and full-frame cameras