How to use the FOV calculator
- Sit the way you fly. Seat height, back rest and the distance you hold the stick or yoke all move your head.
- Measure from between your eyes to the middle of the screen. A tape measure is fine; being 3 cm out changes the answer by a degree or two.
- Enter the screen's diagonal size and shape. The size on the box is the diagonal. Ultrawide 21:9 monitors are usually 3440 × 1440; 32:9 monitors are double-width 16:9.
- Pick the curve. Curved monitors list it as a radius, such as 1800R (the curve of a circle with a 1,800 mm radius). The tighter the curve, the more of your view the same screen covers.
- Choose one or three screens. For three, enter the bezel: the frame on one side between the picture and the monitor's edge.
- Copy the numbers into your sim. The horizontal angle goes into a setting that asks for horizontal field of view; the vertical one into a setting that asks for vertical.
What the numbers mean
Field of view (FOV) is how wide an angle of the world the sim draws on your screen. Your screen also takes up a fixed angle of your own vision, set by its size and how far away you sit. When the two match, the view is at true scale: a runway, a car ahead or the cockpit frame looks the size it would through a real windshield.
Set the sim wider than that and it squeezes more of the world onto the same screen, so everything looks smaller and farther away, and speed feels slower. Set it narrower and the view looks zoomed in.
Some examples, from this calculator:
| Screen | Distance | Horizontal | Vertical |
|---|---|---|---|
| 24″ 16:9 | 60 cm | 47.8° | 28° |
| 27″ 16:9 | 60 cm | 53° | 31.3° |
| 27″ 16:9 | 80 cm | 41° | 23.7° |
| 34″ 21:9, 1800R | 70 cm | 62.1° | 26.8° |
| 49″ 32:9, 1000R | 80 cm | 84° | 23.8° |
| 55″ TV | 120 cm | 53.8° | 31.9° |
| Three 27″ 16:9 | 70 cm | 141° across | 27° |
A single desk monitor covers a narrow slice of your vision, often 40–55° across. That is why true scale on one monitor can feel cramped in a cockpit: the panel and the view out don't both fit.
True scale or wider?
There is no single right answer, and it differs between flight and racing.
- Flight sims. In an airliner or a small plane you need the instruments and the view outside at the same time. On one monitor, true scale often can't fit both, so a slightly wider view is a fair trade; look around with a hat switch, head tracking or the mouse. Start from the calculator's number, then widen it a few degrees at a time until the panel fits.
- Racing sims. Judging braking points and the gap to the car ahead depends on distances looking right, so stay close to true scale and get a wider view from a bigger screen, a closer seat or three screens instead.
- Bigger or closer beats wider. The only way to see more of the world at true scale is for the screen to cover more of your vision: sit closer, go bigger or curved, or add side screens. The calculator shows how far each option moves the angle.
Setting up three screens
- Put all three at the same distance from your eyes. Turn each side screen in by the side screen angle the calculator gives, measured from the line of the center screen. Then each screen faces your eyes square-on, and none looks stretched.
- Close the gap. The angle assumes the side screens' inner edges touch the center screen's edges. Bezels leave a strip with no picture; the calculator counts them, so enter yours.
- Tell the sim. Sims with triple-screen support typically ask for the field of view of one screen (or of all three) plus the angle between them. Use the calculator's per-screen or total figure, whichever the setting asks for.
- In X-Plane 12, run each monitor as its own view: give each the per-screen lateral field of view, and offset the left view by minus the side angle and the right view by plus it. X-Plane's own help describes the same setup: a negative lateral offset on the left monitor, none in the center, a positive one on the right.
If a game can only draw one wide picture across all three screens, it renders a flat image onto angled screens. The edges then look stretched, and the further the side screens are turned, the worse it gets.
Where the setting is in each sim
- X-Plane 12: Settings, Graphics, then the field of view section. The setting is called lateral field of view and is a horizontal angle in degrees. X-Plane's manual says most widescreen monitors will keep the default of 80°. On a 27-inch 16:9 monitor, 80° is true scale only with your eyes about 36 cm from the screen, which is why the default looks wide on most desks.
- MSFS 2024: no setting in degrees. The view is framed by the camera zoom, and each aircraft's maker sets its starting zoom, so the same zoom can look different from one plane to the next. Zoom until the panel looks the size it would from the seat, then save that view as a custom camera.
- Racing sims and other games: look at what the setting is called. If it says horizontal or hFOV, use the horizontal angle; vertical or vFOV, the vertical one. Some games use a slider with no units instead of degrees, and then the calculator's numbers are only a guide.