One Rep Max Calculator - timinvermont.com
Examples: A routine for squats calls for you to do 3 sets of 8 reps. You want to know what a good hard set of 8 reps would be, and you know your current 1 rep max on the squat is 385 lbs. 385 x .786 = 303. You should be able to do an 8 rep set at 303 +/- ...