Data Sources & Methodology

Transparency is the foundation of trust. We don't invent numbers. Every calculator on this site is built on published academic research or official federation rulebooks.

1. One-Rep Max (1RM) Formulas

Our 1RM calculator relies on the consensus of seven published formulas. You can read our deep dive on this in our 1RM Accuracy Guide.

• Epley (1985): Epley, B. (1985). Poundage Chart. Boyd Epley Workout.
• Brzycki (1993): Brzycki, M. (1993). Strength Testing—Predicting a One-Rep Max from Reps-to-Fatigue. Journal of Physical Education, Recreation & Dance.
• Lombardi (1989): Lombardi, V. P. (1989). Beginners Weight Training.
• Lander (1985): Lander, J. (1985). Maximums Based on Rep Performance. National Strength & Conditioning Association Journal.
• Mayhew et al. (1992): Mayhew, J. L., et al. (1992). Relative Muscular Endurance and Fat-Free Weight in Predicting One-Repetition Maximum Bench Press. Journal of Applied Sport Science Research.
• O'Conner et al. (1989): O'Conner, B., et al. (1989). Weight Training: The Ultimate Guide.
• Wathan (1994): Wathan, D. (1994). Load Assignment. NSCA Journal.

2. Powerlifting Scoring Systems

Our scoring calculators (Found Here) use the official coefficients provided by the respective organizations.

• Wilks 2020 (Wilks2): The updated polynomial coefficients published by Robert Wilks in 2020 to correct issues with the original 1994 formula.
• DOTS: The official scoring formula developed by the DOTS project in 2019. It is widely used by OpenPowerlifting and non-IPF federations.
• IPF GL Points: The official Goodlift (GL) scoring system adopted by the International Powerlifting Federation (IPF) in May 2020. We use their specific coefficients for Classic, Equipped, and Bench-Only events.

3. The Plate Loader Algorithm

Our Plate Calculator does not use a simple greedy algorithm (which rounds to the nearest available weight and often overshoots the target). It uses Dynamic Programming, a mathematical method that evaluates thousands of combinations to find the exact closest loadable weight without exceeding the target.

4. Warm-Up Protocols

Our warm-up generator relies on standard strength and conditioning protocols (NSCA guidelines), utilizing a 40/60/75/85/92% ramp-up structure based on the working weight or estimated 1RM.