Assumptions
Calculator assumptions
These tools use simple, explainable formulas so the outputs stay useful as starting points rather than pretending to be exact.
Calorie calculator assumptions
The calorie calculator uses the Mifflin-St Jeor equation to estimate BMR, then multiplies that by an activity factor to estimate maintenance calories.
The fat-loss and muscle-gain targets are percentage adjustments around estimated maintenance rather than personalised coaching recommendations.
Macro calculator assumptions
The macro calculator starts with protein linked to body weight, keeps fat above a practical floor, and gives the remaining calories to carbohydrates.
BMI and deficit assumptions
BMI is a simple height and weight ratio and does not directly measure body composition.
The calorie deficit calculator uses the common rough estimate that 7,700 kcal is about 1 kg of body fat equivalent, but real outcomes vary.
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