Gym Log tools
Training calculators.
Small, practical tools for understanding training data, with the assumptions and sources behind the result kept visible.
Available tools
Strength estimate
One-rep max calculator
Estimate 1RM from a completed set, compare Epley, Brzycki, Lander, Lombardi, Mayhew, O’Connor, and Wathen, and see the range between them.
Open the calculatorBody composition estimate
Body fat calculator
Use U.S. Navy circumference, Jackson–Pollock skinfold, or Durnin–Womersley equations with source ranges, measurement instructions, and original citations.
Open the calculatorEnergy planning estimate
Calorie and macro calculator
Estimate resting and maintenance energy, apply an explicit calorie adjustment, and allocate protein, fat, and carbohydrate with cited methods and auditable arithmetic.
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