Camera & units
Field of View Converter
Direct answer
Horizontal and vertical field of view are linked by the aspect ratio: the tangent of half the horizontal angle equals the tangent of half the vertical angle times the aspect. Unreal's camera FOV is horizontal, Unity's is vertical, so a 90 degree Unreal camera is roughly 59 degrees in Unity at 16:9.
Result
- Horizontal field of view
- —deg
- Vertical field of view
- —deg
- Equivalent 35 mm focal length
- —mm
- Horizontal at the compared ratio (Hor+)
- —deg
- Vertical at the compared ratio (Vert-)
- —deg
Method & assumptions
How this is worked out
The two angles are tied together by the aspect ratio: tan(h/2) = tan(v/2) x aspect. Everything else on this page is that identity rearranged. Note it is not linear, so you cannot simply scale the angle by the aspect ratio, which is the mistake behind most wrong ports.
Hor+ means the vertical view is held constant and a wider screen shows more to the sides; that is the correct behaviour for almost every game, and it is what the compared-ratio figures assume. Vert- holds the horizontal constant and crops the top and bottom, which is what ultrawide players complain about.
The focal length is the full-frame equivalent for a 36 mm wide sensor: f = 18 / tan(h/2). Useful when a cinematographer asks for a 35 mm look and the engine wants degrees.
Common values, converted at 16:9
| Horizontal | Vertical | 35 mm equivalent | Typical use |
|---|---|---|---|
| 60 deg | 35.0 deg | 31 mm | Third person, cinematic |
| 70 deg | 41.7 deg | 25.7 mm | Third person action |
| 90 deg | 58.7 deg | 18 mm | First person default |
| 103 deg | 70.5 deg | 14.4 mm | Competitive shooter |
| 120 deg | 90.0 deg | 10.4 mm | Maximum before heavy distortion |
Above about 110 degrees horizontally, the stretching at the screen edges becomes hard to ignore. It is a projection artefact, not a bug, and no amount of lens correction removes it entirely.
Questions
Is Unreal's field of view horizontal or vertical?
Horizontal. Unreal's camera FieldOfView property is the horizontal angle, while Unity's Camera.fieldOfView is vertical. Porting a camera between them without converting is why a scene that framed correctly in one engine looks zoomed in or out in the other.
How do I convert horizontal FOV to vertical?
Take the tangent of half the horizontal angle, divide by the aspect ratio, and take twice the arctangent. At 16:9 a 90 degree horizontal view works out to about 58.7 degrees vertically.
What field of view should an ultrawide player get?
The same vertical angle as everyone else, with the extra width shown at the sides. That is Hor+, and it means an ultrawide player sees more of the world rather than a cropped version of the same view. Anything else reads as a penalty for owning the monitor.