The one rep max calculator below will help you determine the maximum poundage you can complete without necessarily having to do a one rep max lift. Simply enter the number of reps you can complete with the particular weight used. Once this information is entered, select formula and hit the calculate button.
One Rep Max
One repetition maximum is the maximum weight one can lift on a particular exercise for a single repetition. Apart from being a measure of strength, it is sometimes used to determine fitness level. The one rep max calculation can also help while planning the weight one should lift. Supervision is recommended while performing since it can be dangerous. Testing of strength can be done in a laboratory and different tests have evolved. The one rep max is also known as Maximum Load (1RM).
One Rep Max Chart
Here is a simple chart that you can use.
How to calculate one rep max using the chart above:
weight lifted × chart number (locate under exercise type and reps completed) = one rep max
Let’s take an example of someone who benches 250 lbs for 6 repetitions. The one rep max is calculated as:
250 lbs × 1.18 = 295 lbs (this is the projected one rep max)
Alternatively, another chart has been developed that does not require any calculations.
1 Rep Max Chart
Let’s look at our previous example that we calculated above to see if we obtain similar results.
Weight lifted: 250 lbs for 6 repetitions.
The repetitions appear on the top row while the weights are on the subsequent rows and columns. In our case, we find 250 lbs on the first column (almost at the end of the chart, marked yellow). Then we find the 6th repetition on the first row, move along the column and row until fingers meet in a single cell. In our example, this brings us to 295 (marked red). This is the same 1RM we found earlier.
Some other common formulas for calculating Maximum Load (1RM)
Brzycki’s equation (1993)
1RM = Weight ÷ (1.0278 – (0.0278 × number of repetitions))
Baechle equation (2000)
1RM= Weight × (1 + (0.033 × number of repetition))
1RM = (100 × Weight) ÷ (101.3 – 2.67123 × number of repetitions)
1RM = weight × (1 + 0.025 × number of repetitions)
Mayhew et. al formula
1RM = (100 × Weight) ÷ (52.2 + (41.9 × e-0.055 × number of repetitions))
1RM = (100 × Weight) ÷ (48.8 + (53.8 × e-0.075 × number of repetitions))