MuscleCALC One Rep Max (1RM) Calculator

Calculate your one rep max (1RM) and get estimated rep ranges for 50% 1RM through 100% 1RM. Also see a graphical display of your 1RM and rep ranges.

(Requires Flash to see the chart on this page. You may need to adjust the Flash security settings as well.)

MuscleCALC 1 Rep Max Estimator
Weight Lifted:  
  Repetitions:  (enter a value between 1-10 for accurate results)
One-Rep Max:  
      Estimated Rep Range  
  50% 1RM: 20+  
  55% 1RM: 18-20  
  60% 1RM: 16-18  
  65% 1RM: 14-15  
  70% 1RM: 12  
  75% 1RM: 10  
  80% 1RM: 8  
  85% 1RM: 6  
  90% 1RM: 5  
  95% 1RM: 2-3  

  Muscular Endurance è Muscular Size è Muscular Strength
  The 1 Rep Max Estimator predicts how much weight you should be able to lift for a single repetition (1RM).
  The determination of this value can be used as the basis of your weightlifting program--simply determine your 1RM for each exercise you perform and record this information. The estimator will also provide you with the weight values for each 5% increment, from 50% of your 1RM to 95%. The 50% value is a good weight to use for your warm-ups. Your working weights will probably fall in the 70%-80% range. Over time, your 1RM should be increasing. If it is, then you are getting stronger. For the most accurate results, the repetitions you enter must be between 1 and 10.

(The full MuscleCALC product includes many features, such as the Performance Analyzer and 1 Rep Max Estimator.)


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System Requirements

Requires Microsoft Excel.

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