There are two parts to this calculator.

The first part lets you enter troop counts along with their level, and calculates might. This is handy to calculate how much might is tied up in the infirmary. All troop types have the same might based on level (fighter, rider, shooter, vehicle).

The second part lets you enter a troop might number along with a headquarters level, and guesses at the number of troops. This is a convenient way to estimate troop counts if you can't scout someone.