Calorie Calculator

Find your daily calorie needs for maintenance, weight loss or weight gain using the Mifflin-St Jeor equation.

Your Details

years
cm
kg

Your Results

Maintenance Calories
0 kcal/day
Base Metabolic Rate (BMR)
0 kcal/day
0
Mild Loss (-250)
0
Weight Loss (-500)
0
Extreme Loss (-1000)
0
Mild Gain (+250)
0
Weight Gain (+500)
0
Maintenance
0 g
Carbs (50%)
0 g
Protein (20%)
0 g
Fat (30%)
BMR Calculator BMI Calculator Ideal Height & Weight

How Daily Calorie Needs are Calculated

This calculator uses the Mifflin-St Jeor equation, widely regarded as one of the most accurate formulas for estimating Basal Metabolic Rate (BMR) — the calories your body burns at complete rest.

Men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5

Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161

Your BMR is then multiplied by an activity factor to get your Total Daily Energy Expenditure (TDEE), also called your maintenance calories — the number of calories you'd need to eat daily to keep your weight stable.

Why does a 500 kcal deficit equal about 0.5 kg fat loss a week?

Roughly 7,700 kcal is stored in 1 kg of body fat. A 500 kcal/day deficit adds up to about 3,500 kcal over a week — close to half of that 7,700 kcal figure — which is where the widely used "500 kcal deficit ≈ 0.5 kg/week" estimate comes from. Real results vary with individual metabolism, water retention and how consistently the deficit is held.

How to calculate your calorie targets, step by step

  1. Enter your Gender, Age, Height and Weight.
  2. Choose your typical weekly Activity Level, from Sedentary to Extra Active.
  3. Choose whether you want to Maintain, Lose or Gain weight, and select a deficit/surplus pace.
  4. Click Calculate to see your maintenance calories, goal calories, and a suggested macro split.

Why large deficits and surpluses aren't always better

A moderate deficit (around 500 kcal/day or less), paired with enough protein, tends to preserve muscle while losing mostly fat. Large deficits (1000 kcal/day) push the body to break down muscle alongside fat, make it harder to get adequate protein and micronutrients from a much smaller food intake, and are harder to sustain — they should generally only be used short-term and under supervision. The same logic applies in reverse: a large surplus without resistance training adds mostly fat, not muscle, while a smaller surplus with training tends to produce leaner gains.

Why this macro split?

The default macro split (50% carbohydrate, 20% protein, 30% fat) is a general, balanced starting point suited to typical Indian diets rich in grains and pulses. It's a reasonable default, not a fixed rule — protein needs may be higher for those doing regular strength training.

Disclaimer: These figures are estimates for general awareness only and not medical advice. Please consult a doctor or registered dietitian before making significant changes to your diet.

Frequently Asked Questions

Roughly 7,700 kcal is stored in 1 kg of body fat. A 500 kcal/day deficit adds up to about 3,500 kcal over a week, which is close to half of that 7,700 kcal figure — hence the widely used estimate of about 0.5 kg of fat loss per week at a 500 kcal daily deficit. Real results vary with individual metabolism, water retention and adherence.

Maintenance calories, or Total Daily Energy Expenditure (TDEE), is your BMR (calories burned at complete rest) multiplied by an activity factor reflecting your typical weekly exercise level. This is the number of calories you'd need to eat daily to keep your weight stable — calorie targets for weight loss or gain are then calculated as a deficit or surplus from this number.

Very large deficits can cause your body to lose muscle mass alongside fat, since it's under significant energy stress, and they make it harder to get adequate protein, vitamins and minerals from a much smaller food intake. They're also harder to sustain, increasing the risk of regaining the weight. A large deficit should generally only be used short-term and under professional supervision.

This split is a general, balanced starting point suited to typical Indian diets rich in grains and pulses, providing enough protein for basic muscle maintenance while keeping carbohydrates as the primary energy source. It's a reasonable default, not a fixed rule — people doing regular strength training often benefit from a higher protein percentage.

No — a surplus alone doesn't build muscle without a stimulus like resistance training; without that stimulus, the extra calories are more likely to be stored as fat. Smaller surpluses (a few hundred kcal above maintenance) combined with strength training generally lead to leaner muscle gains than large surpluses, which add more fat alongside the muscle.

A moderate deficit (around 500 kcal/day or less) paired with enough protein and some resistance training tends to preserve muscle while losing mostly fat. A very large deficit, or a deficit with too little protein, pushes the body to break down muscle tissue for energy alongside fat — which is why extreme calorie restriction is generally discouraged for sustainable weight loss.

It doesn't account for individual metabolic variation, hormonal conditions, medications, water retention, or the quality/timing of food eaten — it estimates energy needs from height, weight, age, gender and activity level using population-average formulas. These figures are estimates for general awareness only and not medical advice.
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