There are a few of these Lens Calculators splattered around the interweb and on apps and they are always handy to play with. Shooting 4k, 1080, PAL or NTSC, IMAX or 1/2″ and need to know the DoF or FoV + more then this little lens calculator may be what you need to work it out.
Try the Lens Calculator.
Please see some other online versions like Canon, also AUCOM, and of course the Papa Smurf of them all the AbelCineTech Field of View Calculator.