Macro calculator
Calories and macros for fat loss, maintenance or muscle gain, built from the same engine as the app.
Maintenance
2,500 kcal
starting estimate
Daily target
1,970 kcal
-530 kcal/day
Protein
160 g
2 g/kg
Fat / Carbs
55 / 209 g
How this was calculated: Maintenance ≈ 2500 kcal (estimated with the Mifflin-St Jeor formula and your activity). A -0.6%/week target at 80kg needs a 530 kcal daily deficit. Protein 2 g/kg = 160 g. BMR 1758 kcal. Fat is at least 0.6 g/kg; carbs fill the rest. This is a starting estimate — real expenditure varies by a few hundred calories.
Estimates for healthy adults, not medical advice. If you are pregnant, have a medical condition or a history of disordered eating, speak to a qualified professional first.
Worked example
For an 80kg person at 2,060 kcal: protein 160g (640 kcal), fat at least 0.6 g/kg and about 25% of energy — 57g (515 kcal) — and carbohydrate fills the remaining ~905 kcal, about 227g.
Common questions
- Which macro should I set first?
- Protein first, then a minimum amount of fat for health, then carbohydrate with the remaining calories. Calories decide weight change; macros mainly affect body composition, performance and fullness.
- Is low-carb better for fat loss?
- When calories and protein are matched, low-carb and higher-carb diets produce similar fat loss. Pick the split you can stick to.
- How precise do I need to be?
- Hitting calories and protein within about 10% most days is enough. Consistency across weeks matters more than precision on any one day.
Targets that adapt to your real results, not a one-off calculation.
Fit40Strong starts from these numbers, then learns from what you actually log — and tells you why every time it changes something.
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