Resting energy is estimated with the Mifflin–St Jeor equation, then multiplied by your selected activity level. Fat loss uses a moderate 15% starting deficit.
FREE MACRO CALCULATOR FOR WOMEN OVER 40
Stop guessing.
Find your starting numbers.
Calculate sensible starting points for your calories, protein, carbohydrates, fats and fibre—without chasing somebody else's perfect numbers.
Why I made this
At 63 kg, I was chasing 120 g of protein a day. My 1.6 g/kg starting point was actually 101 g. Once I stopped treating “more” as automatically better, my eating became simpler—and my waist started moving again. That does not prove eating less protein caused it; it showed me that 120 g was never a magic number.
HOW THE CALCULATOR WORKS
Transparent maths. No magic number.
Your centre point is 1.6 g per kg of bodyweight. That sits within the range commonly used by active adults.
Protein is fixed first. Fat receives 25%, 30% or 35% of calories, and carbohydrates receive the remainder.
The result uses the UK adult recommendation of 30 g a day.
This calculator is educational and cannot measure your metabolism or replace personalised advice. Speak to your GP or a registered dietitian before changing your intake if you are pregnant or breastfeeding, have a medical condition, take medication affected by food intake, have a history of disordered eating, or receive an unusually low result.
The calculator uses the Mifflin–St Jeor equation, the British Dietetic Association's active-adult protein guidance, and the UK SACN fibre recommendation. Calories remain an estimate because an activity choice cannot measure your actual daily energy use.