What level does machoke evolve into?

I don't know what level Machoke evolves at, but I know you do have to trade with another person before it will evolve. If it is at a high enough level when you trade it, it will evolve into Machamp. Machop evolves into machoke at lvl 28, then you have to either trade or catch a Machamp in the wild (or cheat) to get it