How calories and macros are calculated

Choose what you want from food planning

Your food plan can support a different goal from your workout plan. You can work on strength while maintaining weight, or focus on training without tracking food. Choosing Lean does not automatically lower your calories.

Choose Calculate my macros and start with your weight, height, age, sex option, usual activity, and nutrition goal. The planner estimates calories, protein, carbs, and fat together. If you already have calorie or macro targets, you can use those instead. Entered targets stay unchanged.

Energy is an estimate

The calorie estimate starts with the Mifflin-St Jeor calculation. It uses your weight, height, age, and the sex option you select, then accounts for the activity level you choose. The result is a rough estimate of the energy needed to maintain your weight, not a measurement of your individual needs.

From that estimate, gradual fat loss starts 10% lower and muscle gain starts 5% higher. Maintenance and strength/performance start at estimated maintenance. Calories round to the nearest 10. These are BuildingRome planning choices, not individually validated requirements. Review energy, recovery, and progress over a few weeks before adjusting. The automatic calculator supports 1,200–6,000 kcal; being inside that range does not establish nutritional adequacy.

Do not count the same training twice through both an activity factor and an additional wearable-calorie allowance. The tool does not add exercise calories separately.

Suggested macros from your calories and weight

BuildingRome uses 1.6 g/kg protein for maintenance or strength and performance, 1.8 g/kg for muscle gain, and 2.0 g/kg for gradual fat loss. These are product starting points within ISSN sports-nutrition ranges, not goal-specific doses proven by a clinical trial. Individual needs vary.

Balanced allocates 30% of your calories to fat; More room for carbs allocates 25%. Carbs fill the remaining energy after protein and fat. Similar goals may produce similar macros. If you choose I know my calories, your entered calories stay unchanged. You can also switch to your own macro targets.

From daily totals to meals

The calculator counts 4 kcal per gram of protein or carbohydrate, and 9 kcal per gram of fat. Enter calories, protein, and fat, and it works out the carbohydrates from the calories left over. If protein and fat already exceed your calories, the tool asks you to adjust your entries.

Choose the number of meals that suits your day. The planner splits your totals evenly as a starting point; you do not need to eat equal meals or follow a particular schedule. Food labels may show different calorie totals because of fiber, sugar alcohols, and rounding.

Start with the routine you can use

Start with meals you enjoy and can prepare regularly. If tracking numbers is not useful for you, choose the habits option. A number accepted by the calculator is not a judgment about whether a diet meets your needs.

People who need medically tailored nutrition, or support around disordered eating, should use an appropriate qualified professional rather than an automatic diet prescription. The estimate and suggested macros exclude pregnancy, breastfeeding, and people under 18.