Question: how to find out how many calories i need in a day?
Answer: Step 1: Find your body weight in kilograms (if you live in the US, just divide your weight in pounds by 2.2 to get your weight in kilograms).
Step 2: Multiply your weight in kilograms by 0.9 if you are a woman or 1.0 if you are a man.
Step 3: Multiply by 24.