Bench Press Calculator

You can use our free bench press calculator to quickly and easily determine your one-rep max in accordance with the number of repetitions you have completed for a given weight.

To calculate your one-rep max using our bench press calculator, complete the following simple steps:

  • Input the weight you lifted (pounds/kilograms)
  • Choose the equation you wish to use to calculate your one-rep maximum (1RM)
  • Input the number of reps you completed
  • Click on the "Calculate" button to observe the results.

What is the one-rep max?

The one-repetition maximum, which is also referred to as the maximum load (1RM), is the highest weight you can lift for a given exercise for a single repetition. In addition to representing a strength measurement, it can also be employed to determine your level of fitness and/or help to plan how much weight you can lift during a training session.

1RM Bench Press Calculator

lbs/kg

Why is the one-rep max important?

There are two main reasons as to why you may wish to identify your one-rep maximum:

  1. It is a very useful measure that provides you with an indication of how much weight you should be lifting to attain your fitness goals. For example, if your training objectives are to increase your build strength and size, you should aim to lift a minimum of 60% of your body weight in a one-rep max. If your objective is to enhance your tone and endurance, you should aim to lift between 30 and 60 percent of your one rep max.
  2. It can be a useful measurement of how strong you are. You can use it to compare your strength with those of your training partners, and it can also provide you with an indication of how strong a distinct muscle is.

1RM Equations & Calculation Example

There are a few different methods of calculating your one rep max. The most common approaches are as follows:

Brzycki: 1 RM = w / (1.0278 - (0.0278 × r))

Baechle: 1 RM = w × (1 + (0.033 × r))

Epley: 1 RM = (0.033 × r × w) + w

Lander: 1 RM = (100 × w) / (101.3 - 2.67123 × r)

Lombardi: 1 RM = w × r 0.1

Mayhew et al.: 1 RM = (100 × w) / (52.2 + (41.9 × e-0.055 × r))

O'Conner et al.: 1 RM = w × (1 + 0.025 × r)

Wathan: 1 RM = (100 × w) / (48.8 + (53.8 × e-0.075 × r))

Where, 1RM is the one repetition maximum, w is the weight lifted, r is the number of repetitions, e is the base of the natural logarithm = 2.718282

Example: In this example, we use the Brzycki equation to calculate the one-rep max (1RM) for someone who performs 10 reps lifting 135 lbs. This calculation is as follows:

w = 135, r = 10

1 RM = w / (1.0278 - (0.0278 * r))

1 RM = 135 / (1.0278 - (0.0278 * 10))

1 RM = 135 / (1.0278 - 0.278)

1 RM = 135 / 0.7498

1 RM = 180.05 lbs

As such, the 1RM for an individual who lifts 135 lbs. over 10 reps is 180.05 lbs.

You may also want to check out the APFT Calculator (Army Physical Fitness Test Calculator)

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