How this calorie calculator works
First it estimates your basal metabolic rate (BMR), the energy your body uses at rest, with the Mifflin-St Jeor equation (1990), which studies have found to be among the most reliable for healthy adults:
- Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
- Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
Then it multiplies BMR by an activity factor (1.2 for sedentary up to 1.9 for very active) to estimate your total daily energy expenditure (TDEE), the calories you burn on a typical day.
Finally it adjusts for your goal: about 500 kcal below TDEE to lose roughly 0.5 kg (1 lb) a week, 250 kcal below for a gentler pace, or 250 kcal above to gain slowly.
Use the result as a starting point
Equations estimate the average person of your size; you are not average. Eat to the target for two to three weeks, watch your weight trend and adjust by 100 to 200 kcal if needed. Very low targets are hard to keep and can leave you short on nutrients, so the calculator warns you below 1,200 kcal (women) or 1,500 kcal (men).
This calculator is for healthy adults. It is not suitable during pregnancy or breastfeeding, for children, or if you have a medical condition; ask your doctor or a dietitian.
From a number to a habit
A target only helps if you track against it. Yumi sets your calories and macros from the same kind of inputs and lets you log meals with a photo, then adapts the target as your weight changes.
