This simple calculator is used to calculate your 1 rep max for maximum output in the gym! Simply enter a weight you've lifted for a certain amount of reps and see your results dynamically displayed on the screen.

Utilizing the Brzycki Formula, this 1RM calculator will allow you to get an accurate estimate of how much weight you can lift relative to a heavy exercise set of 10 reps or less. Please note that for the most accurate 1RM estimates, sets of lower repetitions are more accurate than sets of repetitions closer to 10.