[Hethj7]

Here is the formula to figure tire diameter and what your's is:

On a 245/50/16 tire:

245 * .5 *2 / 25.4 = 9.64567 (this is tire width in mm * ratio of sidewall height to width *2 to account for a sidewall above and below the rim / 25.4 to convert mm into inches)

then add the rim size, so 9.64567 + 16 = 25.6457 inches is your tire diameter