Fitness and Bodybuilding Calculators

Choose the Right Tool

Match the Calculator to the Decision You Need to Make

Start with the question, then choose the calculator built for it. Strength estimates can guide loading, nutrition estimates can turn a calorie target into workable ranges, body-composition tools can add context to repeatable measurements, and the volume calculator can expose how a programme distributes training across muscle groups.

Strength

Bench Press / 1RM Calculator

Compare two established rep-max formulas and turn one controlled bench press set into a practical estimated range.

Determines: Estimated bench press 1RM, the range between Epley and Brzycki, and percentage-based training loads.
Inputs: Weight lifted, repetitions completed, and kilograms or pounds.
Useful for: Planning conservative loads for powerlifting, 5x5 and Wendler 5/3/1 training.
Main limitation: Rep-based formulas are estimates. Fatigue, technique and higher-repetition sets can widen the error.

Open Bench Press Calculator

Body Composition

Body-Fat Percentage Calculator

Use standardized circumference measurements to estimate body-fat percentage and view a realistic uncertainty range.

Determines: A circumference-based body-fat estimate, uncertainty range and optional fat and fat-free mass.
Inputs: Male or female measurements, metric or imperial units, height, neck, waist or abdomen, hips for women, and optional body weight.
Useful for: Tracking body-composition trends when the same tape method and conditions are repeated.
Main limitation: Tape equations inherit landmark and measurement error and do not provide a diagnosis or direct scan.

Open Body-Fat Calculator

Nutrition

Macro Calculator

Turn an existing calorie target into evidence-informed protein, fat and carbohydrate ranges.

Determines: Daily protein, fat and carbohydrate ranges plus the calories contributed by each macronutrient.
Inputs: Manual or imported calorie target, body weight, goal, units and higher-carbohydrate or higher-fat preference.
Useful for: Converting a calorie target into workable macro ranges for muscle gain, fat loss or maintenance.
Main limitation: It does not calculate TDEE, and no single macro split is perfect for every person or situation.

Open Macro Calculator

Body Composition

FFMI Calculator

Estimate fat-free mass and compare FFMI with a height-normalized value and body-fat sensitivity range.

Determines: Estimated fat-free mass, FFMI, normalized FFMI and the effect of body-fat estimation error.
Inputs: Height, weight, estimated body-fat percentage, and metric or imperial units.
Useful for: Adding height-adjusted context to repeatable body-composition tracking.
Main limitation: The result inherits body-fat error and cannot prove steroid use, define a natural limit or diagnose anything.

Open FFMI Calculator

Programming

Workout Volume Calculator

Map exercises to muscles and see how direct, secondary and weighted sets are distributed across a week.

Determines: Direct and secondary weekly sets, weighted volume, seven-day distribution and relative muscle emphasis.
Inputs: Exercises, sets per workout, weekly frequency, muscle mappings, and editable direct and secondary weights.
Useful for: Comparing programme balance and spotting muscle groups with relatively low or high represented volume.
Main limitation: It is a programming estimate and does not account fully for effort, load, technique, recovery or individual response.

Open Volume Calculator

Energy Needs

TDEE Calculator

Estimate daily energy expenditure and starting calorie ranges for maintenance, fat loss and muscle gain.

Determines: Estimated basal metabolic rate, maintenance calories, and starting fat-loss and muscle-gain ranges.
Inputs: Gender, age, body weight, height, activity level, and metric or imperial units.
Useful for: Choosing a starting calorie target that can be imported directly into the Macro Calculator.
Main limitation: Equation and activity estimates vary from real expenditure, so the result needs checking against intake and body-weight trends.

Open TDEE Calculator