LensCalc

Focal Length Equivalent Calculator

What's the full-frame equivalent of this lens?

Focal Length (mm)

Crop Factor

Equivalent Focal Length

52.5 mm

Effective FOV: 44.8°

What you entered

Focal Length (mm): 35Crop Factor: 1.5

1
Equivalent focal length
35 mm x 1.5= 52.5 mm
2
Effective diagonal FOV
2 x arctan(43.27 / (2 x 52.5))= 44.7895deg

Result

Equivalent Focal Length: 52.5 mm

Full-frame equivalent focal lengths

Multiply the lens focal length by the sensor's crop factor to get the full-frame focal length that frames the same way.

Lens	Crop factor	Equivalent focal length	Diagonal field of view
24 mm	2	48.0 mm	48.52 deg
35 mm	1.5	52.5 mm	44.79 deg
50 mm	1	50.0 mm	46.79 deg
50 mm	1.5	75.0 mm	32.18 deg
50 mm	1.6	80.0 mm	30.26 deg
50 mm	2	100.0 mm	24.41 deg
85 mm	1.6	136.0 mm	18.08 deg
200 mm	1.5	300.0 mm	8.25 deg

A 35mm lens on APS-C is the classic 'normal' setup, framing almost exactly like a 50mm on full frame. This is why 35mm primes are so common in crop-sensor kits.

Equivalent focal length = actual × crop factor

A 35mm lens on a 1.5x crop sensor gives a 52.5mm equivalent — you get the same field of view as a 52.5mm lens would give on a full-frame camera, which is why crop-sensor kits often ship with an 18-55mm lens (equivalent to ~27-82mm).

This only describes field of view

The 'equivalent' focal length describes framing only — it doesn't change the lens's actual depth of field, distortion, or perspective characteristics, which are properties of the physical focal length and subject distance.

Frequently asked questions

I have an 18-55mm kit lens on a 1.6x Canon APS-C — what's the equivalent range?

18 × 1.6 = 28.8mm at the wide end, 55 × 1.6 = 88mm at the long end. So your kit lens frames like a 29-88mm lens on full frame — a versatile range from moderate wide-angle to short telephoto.

How is focal length equivalent different from crop factor?

The crop factor calculator finds the multiplier from sensor dimensions. This calculator applies a known crop factor to a specific lens focal length — it's the next step, turning the abstract ratio into a concrete equivalent you can compare across systems.

Does the equivalent focal length affect bokeh?

No. A 50mm f/1.8 on a crop sensor frames like 75mm but still produces the DOF and bokeh of a 50mm f/1.8. To match the DOF of a 75mm f/1.8 on full frame, you'd need to use f/1.2 on the 50mm crop-sensor setup.

What full-frame equivalent gives a 'normal' perspective?

A 50mm equivalent is traditionally considered 'normal' — close to the human eye's central field of view. On APS-C (1.5x), that means using a ~33mm lens; on Micro Four Thirds (2x), a 25mm lens.