Field of View Calculator
Get the horizontal, vertical and diagonal angle of view for any focal length and sensor, the scene width at a distance and the full-frame equivalent lens.
The interactive tool loads here when JavaScript runs.
About this toolWhat is the Field of View Calculator?
This field of view calculator turns a focal length and a sensor size into the angle a lens sees, horizontally, vertically and across the diagonal. Add a subject distance and it shows the width and height of the scene in the frame, which answers the practical questions: will the whole building fit, how wide a stage does the camera cover from the back of the hall, and how big will a bird be in the frame.
It also gives the crop factor and full-frame equivalent focal length for APS-C, Micro Four Thirds, 1-inch and medium-format sensors, and works backwards to the focal length that fills the frame with a scene of a given width. A table lists common lenses on your sensor.
- Horizontal, vertical and diagonal angle of view
- Scene width, height and diagonal at any distance in metres or feet
- Crop factor and full-frame equivalent focal length
- Reverse mode: focal length to fill a given width
- Sensor presets plus custom sizes and a lens comparison table
- Top-down diagram of the horizontal angle
How to use the Field of View Calculator
- Choose your sensor format, or Custom to enter its width and height in millimetres.
- Enter the actual focal length of the lens.
- Optionally enter the distance to your subject in metres or feet to see the scene width and height.
- Read the horizontal, vertical and diagonal angles and the full-frame equivalent.
- To pick a lens, enter the width you want to fill at that distance and read the focal length suggested.
Worked examples
Normal lens on full frame
Input
36 × 24 mm, 50 mm, 10 m
Output
39.6° × 27.0°, 46.8° diagonal; covers 7.2 × 4.8 m
Width = 10 × 36 ÷ 50. Every doubling of distance doubles the coverage.
Same lens on APS-C
Input
23.5 × 15.6 mm, 35 mm
Output
37.1° horizontal; 53.7 mm full-frame equivalent
The crop factor of 1.53 makes a 35 mm frame much like a 50 mm on full frame.
Lens to frame a stage
Input
Full frame, stage 12 m wide, camera 30 m away
Output
About 90 mm
f = distance × sensor width ÷ scene width = 30 × 36 ÷ 12. An 85 mm lens leaves a little room.
Background and insight
For a rectilinear lens focused at infinity, the angle of view across a sensor dimension d is 2 × atan(d ÷ 2f). On a 36 × 24 mm sensor a 50 mm lens therefore covers 39.6° horizontally, 27.0° vertically and 46.8° diagonally. Lens makers quote the diagonal figure, which is why a 24 mm is sold as an "84° lens" although it covers 73.7° across the long side.
The same geometry scales to the scene: at distance D the frame covers D × d ÷ f. A 50 mm lens on full frame at 10 m spans 7.2 m by 4.8 m. Crop factor is the ratio of the full-frame diagonal (43.27 mm) to the sensor diagonal, and the equivalent focal length is the real focal length multiplied by it, so a 35 mm lens on 23.5 × 15.6 mm APS-C frames like a 53.7 mm lens on full frame.
Equivalence describes framing, not the lens itself: the 35 mm lens keeps its own focal length, perspective from a given spot and f-number. Close focusing narrows the angle slightly because the lens moves away from the sensor (the image distance becomes f × (1 + m)), and fisheye lenses follow a different projection, so the calculator states that it assumes a rectilinear lens at infinity focus.
Common use cases
Choosing a lens before buying
See exactly how much wider a 16 mm is than a 24 mm on your camera.
Event and stage coverage
Work out which focal length frames a stage, a pitch or a wedding aisle from where you can stand.
Real estate and architecture
Check whether a room or facade fits from the space you have.
Security and machine-vision cameras
Find the scene width a sensor and lens cover at a mounting distance.
Switching systems
Translate full-frame focal lengths you know into APS-C or Micro Four Thirds equivalents.
Tips and limitations
- Check whether a spec sheet quotes diagonal or horizontal field of view before comparing lenses or action cameras.
- Video modes often crop the sensor. Enter the recorded area as a custom sensor to get the real view.
- Phone cameras list equivalent focal lengths; use the full-frame preset with those numbers to compare them directly.
- Focus breathing changes framing in video; a lens can look a few degrees narrower at close focus.
- Perspective depends on where you stand, not on focal length. A longer lens only crops the same view.
Frequently asked questions
How do you calculate angle of view?
Angle = 2 × atan(sensor dimension ÷ (2 × focal length)). Use the sensor width for horizontal, height for vertical and the diagonal for the figure lens makers quote.
What is the field of view of a 50mm lens?
On full frame 39.6° horizontal, 27.0° vertical and 46.8° diagonal. On APS-C with a 1.53 crop it is about 26.4° horizontal.
What does crop factor do to focal length?
Nothing to the lens itself. It narrows the view, so a lens frames like one crop-factor times longer on full frame: 25 mm on Micro Four Thirds frames like about 50 mm.
How wide is the area a lens covers at a distance?
Width = distance × sensor width ÷ focal length. A 24 mm lens on full frame covers 15 m across at 10 m.
Why does my camera show a narrower view in video mode?
Many cameras record video from a cropped area of the sensor or add electronic stabilisation, which crops further. Enter the cropped dimensions as a custom sensor.
What focal length matches human vision?
It depends on the definition. The central area we pay attention to is often compared with a 40 to 50 mm lens on full frame, while total peripheral vision spans much more than any rectilinear lens.
Is there an in-depth guide to the Field of View Calculator?
Yes. “Field of View and Crop Factor: What a Lens Really Sees” covers the background, how it works, common pitfalls and worked examples. Read the full guide.
People also search for
- angle of view of a 50mm lens on full frame
- horizontal field of view of 35mm on aps-c
- how wide an area does a 24mm lens cover at 10 metres
- what focal length to fill the frame with a 5 metre wide subject
- full frame equivalent of 25mm on micro four thirds
- difference between diagonal and horizontal angle of view
- field of view calculator for a 1 inch sensor
- what lens matches the human eye field of view
Related Tools You May Like
Free, in-browser tools that pair well with this one.