Why are my needs different from friends of same size?
Age, sex, muscle mass, metabolism, and activity patterns all vary individually by 10-20%.
Health Fitness
Calorie Intake Calculator
Calculate calorie intake with your details.
Personalized estimate
Use realistic inputs for the most useful results.
What this calculator does
Daily calorie intake is total energy needed to maintain weight, accounting for BMR and activity level. Harris-Benedict or Mifflin-St Jeor equations provide estimates.
How it works
Calculate BMR, multiply by activity factor. Total includes all beverages and 20% from food water content.
Formula
Harris-Benedict: Different coefficients for age, sex, weight, height. Activity factors 1.2-1.9.
Tips for using this calculator
- Use as baseline, adjust based on 2-3 weeks of results
- Increase gradually when raising activity level
- Metabolism changes with age, muscle, and hormones
- Thermic effect of food burns 10% of calories
- Track intake for a week to compare estimate to reality
Frequently asked questions
Should I eat same calories daily?
Not necessarily. Many adjust based on activity level. Weekly consistency matters more than daily.
Why do online calculators differ?
Different equations (Harris-Benedict, Mifflin-St Jeor) produce slightly different results. Individual variation is ±15-20%.