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Health & Fitness

Calorie Calculator

A fast and accurate calorie calculator to estimate your daily energy needs using BMR and TDEE, perfect for weight loss, maintenance, or healthy weight gain.

Calculate Your Daily Calories
Enter your details to get accurate calorie recommendations

If provided, we'll use the more accurate Katch-McArdle formula

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What Is a Calorie Calculator?

A Calorie Calculator helps you estimate how many calories your body needs each day based on your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). These estimates guide you in setting calorie targets for weight loss, muscle gain, or weight maintenance. Although this tool is not a substitute for medical advice, it is one of the most practical ways to understand your daily energy requirements and build healthier eating habits.

What Is BMR & TDEE?

Understanding BMR and TDEE is essential before using any calorie calculator.

Basal Metabolic Rate (BMR)

Definition: Calories Burned at Complete Rest

Your Basal Metabolic Rate is the number of calories your body burns simply by staying alive — breathing, circulating blood, digesting food, repairing cells, and maintaining body temperature. These are the calories required if you stayed in bed all day.

Why BMR Matters

Your BMR forms the foundation of all calorie calculations. Every diet plan, whether for fat loss or muscle gain, starts with understanding BMR because it represents your minimum energy requirement.

Scientific Formulas Used to Calculate BMR

Mifflin–St Jeor Equation (Most Accurate for General Population)

This is widely accepted as the most reliable equation for modern lifestyles.

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

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

Harris–Benedict Equation (Older but Still Common)

This formula has been used since 1918 but can sometimes overestimate calorie needs.

Katch–McArdle Formula (For Athletes)

This formula relies on body fat percentage for more accuracy in athletic individuals.

BMR = 370 + (21.6 × lean body mass kg)

Total Daily Energy Expenditure (TDEE)

Definition: Calories Burned in an Entire Day

TDEE is the total number of calories you burn in a full day, including:

  • BMR (resting calories)
  • NEAT (Non-Exercise Activity Thermogenesis - small daily movements)
  • EAT (Exercise-related Activity Thermogenesis)
  • TEF (Thermic Effect of Food - calories needed to digest meals)

Activity Multipliers Explained

TDEE = BMR × Activity Multiplier

Sedentary: Little to no exercise × 1.2

Lightly Active: Exercise 1–3 days/week × 1.375

Moderately Active: Exercise 3–5 days/week × 1.55

Very Active: Exercise 6–7 days/week × 1.725

Extremely Active: Intense training twice daily × 1.9

Choosing the correct activity level is crucial; overestimating leads to higher calorie predictions.

Visual breakdown of Total Daily Energy Expenditure showing BMR as the largest component at 60-70%, followed by NEAT at 15-30%, and smaller portions for exercise and food digestionTDEE Components BreakdownTotal Daily Energy Expenditure (TDEE) = 100%Basal Metabolic Rate (BMR)60-70% of TDEECalories burned at rest (breathing, circulation, cell production)Non-Exercise Activity Thermogenesis (NEAT)15-30% - Daily movements like walking, fidgeting, standingExercise Activity (EAT)5-10% - Planned workoutsThermic Effect of Food (TEF)~10% - Energy to digest food

TDEE is calculated by adding your BMR to all activity-related energy expenditure. BMR represents the majority of calories burned daily for most people.

Calorie Deficit & Calorie Surplus Explained

Calorie Deficit (for Weight Loss)

A calorie deficit occurs when you eat fewer calories than your TDEE. Typical deficits:

  • Moderate: 300–500 calories/day
  • Aggressive (short-term only): 600–800 calories/day
Calorie Surplus (for Muscle Gain)

A surplus occurs when you consume more calories than your TDEE. Typical surpluses:

  • Lean bulk: +200–300 calories/day
  • Aggressive bulk: +400–600 calories/day

Consistency matters more than the size of the deficit or surplus.

Interactive calorie balance scale visualization showing how eating more or less than your TDEE affects weight change through deficit, maintenance, or surplusEnergy Balance: The Foundation of Weight ChangeCalories In🍽️Calories Out🏃Calorie DeficitEat < TDEEWeight LossMaintenanceEat = TDEEMaintain WeightCalorie SurplusEat > TDEEWeight GainCurrent: Maintenance (Stable Weight)

Click each option to see how the energy balance scale tips. Weight change is fundamentally determined by the balance between calories consumed and calories expended.

Step-by-Step Guide

1
Enter Your Age, Gender, Height, and Weight

These details allow the calculator to compute your BMR using the correct formula.

2
Add Body Fat % (Optional)

If you know your body fat percentage, enter it for more accurate results using the Katch-McArdle formula.

3
Select Your Activity Level

Choose the level that best matches your weekly routine.

4
Review Your BMR and TDEE Results

You'll see how many calories your body burns at rest (BMR) and throughout the day (TDEE).

5
Choose Your Goal

Select from weight loss options, maintenance, or muscle gain goals.

6
Get Personalized Daily Calorie Targets

The calculator adjusts your TDEE to show how many calories to eat based on your chosen goal.

7
Apply and Track Your Results

Follow your calorie target, track your intake, and reassess every few weeks.

Real Examples with Numbers

Example 1: Office Worker Seeking Weight Loss

Gender: Female • Age: 30 • Height: 165 cm • Weight: 70 kg • Activity: Lightly Active

BMR (Mifflin–St Jeor): ~1500 calories

TDEE: 1500 × 1.375 = 2060 calories/day

Calorie Targets:

  • Weight loss: 1560–1760 calories
  • Maintenance: 2060 calories
  • Weight gain: 2260–2460 calories
Example 2: Active Male Training 4 Days/Week

Gender: Male • Age: 28 • Height: 180 cm • Weight: 80 kg • Activity: Moderately Active

BMR: ~1750 calories

TDEE: 1750 × 1.55 = 2712 calories/day

Calorie Targets:

  • Weight loss: 2210–2410 calories
  • Maintenance: 2710 calories
  • Weight gain: 2910–3210 calories

Science Behind the Formulas

Comparing BMR Equations

Mifflin–St Jeor Equation

Pros:

Developed in 1990 • Most accurate for modern populations • Ideal for general use • Error margin ~5–10%

Cons:

None significant

Harris–Benedict Equation

Pros:

Developed in 1918 • Updated in 1984 • Familiar, simple • Useful for traditional models

Cons:

Slightly overestimates calorie needs

Katch–McArdle Formula

Pros:

Requires body fat percentage • Most accurate for athletes • Ideal for lean individuals

Cons:

Requires body fat % measurement

How to Apply Your Results

Meal Planning Basics

Focus on Whole Foods: Lean proteins, whole grains, fruits, vegetables, and healthy fats.

Balance Macros: A common ratio is Protein: 25–30%, Carbs: 40–50%, Fats: 20–30%

Protein Intake Matters: Aim for 0.7–1.0g per lb body weight. Higher when cutting calories.

Choose Sustainable Approaches: Extreme diets rarely work long-term.

Tips for Sustainable Change
  • 1Track your intake for at least 2–3 weeks
  • 2Make small, consistent adjustments
  • 3Stay hydrated
  • 4Strength training preserves muscle during dieting
  • 5Recalculate your needs every 2–3 months

Limitations & Accuracy

While calorie calculators are helpful, keep in mind:

  • They provide estimates, not exact numbers
  • Accuracy depends heavily on honest activity level selection
  • Water retention can hide fat loss
  • Genetics, hormones, and metabolism vary greatly between individuals
Safety Disclaimer

This calorie calculator provides general estimates only and should not replace professional medical or nutritional advice. Individuals with medical conditions should consult a healthcare provider before making significant dietary changes.

Frequently Asked Questions