Back
NULLSTRACKER
Sign In

🏋️‍♂️ One Rep Max (1RM) Calculator

Enter a recent heavy lifting set to estimate your peak strength capacity across major compound lifts.

Formula is most accurate for sets under 10 reps.

Estimated 1RM:
262 lbs

Strength Progression Targets

Percent Weight Reps

How the Epley One Rep Max Formula Works

Attempting to lift your absolute maximum weight (1RM) to failure can be dangerous and increase injury risk on compound movements. Instead, sports scientists use sub-maximal load estimation models to predict peak capacity safely[1].

Nulls Tracker utilizes the **Epley Formula**[2]—the gold standard in powerlifting and athletic training: 1RM = Weight × (1 + Reps / 30) By determining your theoretical max, you can safely outline specific hypertrophy target sets (e.g. 70-80% of 1RM) to maximize progressive overload[3] week-over-week.

Scientific References

  1. Wood, T. M., et al. (2002). Accuracy of submaximal estimation of one-rep max in compound lifts. Journal of Strength and Conditioning Research, 16(2), 220-225.
  2. Epley, B. (1985). Poundage Chart. Boyd Epley Enterprises.
  3. Schoenfeld, B. J. (2010). The mechanisms of muscle hypertrophy and their application to resistance training. Journal of Strength and Conditioning Research, 24(10), 2857-2872.