Camera calculator · free in CineMath
Focal Length Match Calculator
Find the lens that gives the same horizontal view on a different sensor width.
Focal Length Match answers "what lens gives me the same shot on the other camera?". It matches the horizontal field of view between two sensor widths and gives the crop factor between them. Enter the recorded width of each camera's mode, since a crop or 16:9 mode often uses less of the sensor than its headline size.
Worked examples
| From | To | Equivalent lens | Crop factor |
|---|---|---|---|
| 50 mm on full frame (36 mm wide) | Super 35 (24.89 mm wide) | 34.6 mm | 1.45× |
| 85 mm on full frame (36 mm wide) | Micro Four Thirds (17.3 mm wide) | 40.8 mm | 2.08× |
| 32 mm on Super 35 (24.89 mm wide) | Full frame (36 mm wide) | 46.3 mm | 0.69× |
| 24 mm on Super 35 (24.89 mm wide) | Micro Four Thirds (17.3 mm wide) | 16.7 mm | 1.44× |
What you enter
- Original focal length (mm), with presets 24, 35, 50, 85, 100 and 135
- Original sensor width (mm), with presets 36, 24.89, 23.6, 22.3, 17.3 and 13.2
- Target sensor width (mm), with the same presets
What you get
- Equivalent focal length (mm)
- Crop factor between the two sensors
- The formula with your numbers in it
How CineMath works it out
- Equivalent focal length = focal length × (target width ÷ original width)
- Crop factor = original width ÷ target width, so it is between your two cameras; enter 36 mm as the original width for the usual full-frame crop factor
- Matches on width, so the horizontal field of view is the same; enter heights or diagonals in the two fields to match on those instead
- Matches framing only: depth of field differs between formats at the same stop, while exposure does not
Guides
More Camera calculators
- Depth of FieldNear and far focus limits, hyperfocal distance, and the stop that holds two subjects in focus.
- Field of ViewHorizontal, vertical and diagonal angle of view, and frame coverage at any distance.
- ExposureEnter a stop change and see the iris, shutter angle, ISO or ND that compensates for it.
- Close FocusMagnification, effective aperture and light loss for extension tubes; new close-focus distance for diopters.
- AnamorphicDesqueezed aspect ratio and horizontal-equivalent spherical focal length for any squeeze.