The above formulas help as a guide... but the contract and work rules are necessary to truly understand how much you will make... You can get $56/hr and take home $44,000/year with a worthless contract (I did). Or you can take home $53,000/year at $36/hr with a better contract (I also did). And yes... those numbers do include per diem but at the end of the day all we are talking about is what is listed on the W2 isn't it?