How many calories do I actually need each day?

A calorie is a unit of energy: food holds it and your body spends it every day, even at rest. Public guidance quotes averages of about 2,500 kcal for men and 2,000 for women, but your own number depends on age, size and movement.

Put in your age, height, weight and activity to get a maintenance estimate using the Mifflin-St Jeor formula, plus an example of how a day's calories could be split. It's an estimate, not medical advice.