he number of calories you need depends on 3 main things:

  1. Your size (height, weight, age)
  2. Your activity level (do you sit all day or move a lot?)
  3. Your goal (stay the same weight, lose fat, or gain muscle)

To measure Calculate Your BMR

Let’s simplify with a daily example:

  • If you’re just lying in bed all day doing nothing, your body still burns calories to keep your heart beating, lungs breathing, and brain working. This is called BMR (Basal Metabolic Rate).
  • When you get up, walk around, do work, exercise — that adds more calorie burn.

Estimated Calorie Needs per Day (just a rough idea):

Person Type Calories per day
Child (10 years old) ~1,600–2,200
Average Adult Woman (light active) ~1,800–2,000
Average Adult Man (light active) ~2,200–2,500
Active Adults (workout daily) ~2,500–3,000+

👉 If you want to lose fat, eat about 300–500 calories less than your need.
👉 If you want to gain muscle, eat about 300–500 calories more with strength training.

Easiest way to find your calorie need?

Use this basic calculator:
Your weight (kg) × 22 = your base calories (for no activity)
Then, multiply based on how active you are:

Activity Level Multiply by
Sedentary (little activity) 1.2
Lightly active 1.4
Active (exercise 3–5 days/week) 1.6
Very active (daily workouts/manual work) 1.8–2.0

Example:

If you weigh 70 kg and are moderately active:

  • Base = 70 × 22 = 1,540
  • Activity = 1,540 × 1.6 = ~2,460 calories/day

That’s what you need to maintain weight.

Funda for life:
“Calories are your body’s fuel. Learn your number, then decide:
Want to lose fat? Eat a bit less.
Want to grow muscle? Eat a bit more — with training.”