Evidence-Based Calculation Suite

Nutrition & Metabolic Calculators

Free, mathematically precise dietary tools powered by peer-reviewed physiological equations. Calculate your resting burn, total energy needs, macro distributions, and hydration targets in seconds.

Learn more about our underlying formulas on our Calculation Methodology page.

Mifflin-St Jeor Validated

Zero Signups Required

Metric & Imperial Units

Mifflin-St Jeor Equation (Gold standard)

BMR Calculator (Mifflin-St Jeor)

Calculate your Basal Metabolic Rate — the minimum calories your body burns at complete rest.

Primary Use: Find your baseline energy floor before accounting for physical movement or workouts.

Open BMR Calculator

FAO/WHO Physical Activity Level Multipliers (1.2–1.9)

TDEE Calculator (Total Daily Energy)

Discover your Total Daily Energy Expenditure across BMR, daily movement, digestion, and exercise.

Primary Use: Identify your exact maintenance calories to maintain current weight without fat gain.

Open TDEE Calculator

Atwater Energy System (4 kcal/g protein & carbs, 9 kcal/g fat)

Macro Calculator (Protein, Carbs, Fats)

Determine your optimal daily macronutrient ratio in grams for fat loss, muscle gain, or maintenance.

Primary Use: Distribute calories into actionable grams of protein, carbs, and healthy fats across daily meals.

Open Macro Calculator

Dynamic Energy Balance Model (15–25% deficit)

Calorie Deficit Calculator

Calculate a safe, sustainable daily calorie deficit to hit your target weight without metabolic slowdown.

Primary Use: Set realistic weekly fat loss timelines while preserving lean muscle mass and thyroid signaling.

Open Calorie Calculator

33ml/kg baseline + activity sweat rate adjustments

Daily Water Intake Calculator

Calculate your personalized daily hydration requirement based on body mass, exercise intensity, and climate.

Primary Use: Maintain cellular osmolality, prevent dehydration headaches, and optimize cognitive performance.

Open Daily Calculator

Calculation Disclaimer: All tools and estimates provided are for educational and nutritional planning purposes only. They do not constitute medical advice or clinical diagnoses. Always consult a qualified physician or healthcare provider before embarking on a significant caloric or exercise program. Review our full Medical Disclaimer and Calculation Methodology.

Turn Your Numbers Into a 7-Day Meal Plan

Take your calculated calories and macros and generate a complete weekly grocery schedule with authentic regional meals and local prices.

Generate Free 7-Day Meal Plan