Calorie Calculator

Calorie Calculator

Calculate your Total Daily Energy Expenditure (TDEE) and target caloric deficit/surplus splits instantly using local browser memory.

Input Methodology

1. 1Enter Age: Your current age in years (10–90 range).
2. 2Select Gender: Choose male or female (biological sex affects the BMR formula constant).
3. 3Enter Weight and Height: Input your current weight (kg) and height (cm).
4. 4Select Activity Level: Choose the option that best describes your weekly exercise pattern honestly.
5. 5Review Results: See your TDEE and goal-adjusted calorie targets.

Calorie Calculator — Daily Calorie Target (TDEE)

If your calculated Basal Metabolic Rate (BMR) is 1,600 calories and you lead a moderately active lifestyle, your Total Daily Energy Expenditure (TDEE) is roughly 2,200 calories. To lose half a kilogram (1 pound) of fat per week, standard guidelines recommend maintaining a 500-calorie daily deficit, making your target intake 1,700 calories. This tool models those calorie goals.

• TDEE Seems Too Low: Verify that height is entered in centimetres and weight in kilograms. A common mistake is entering height in metres (1.75) instead of centimetres (175).
• Fat Loss Target is Below 1,200 kcal: If TDEE is very low (e.g. small, sedentary individual), do not reduce below minimum safe thresholds. Consult a dietitian.
• Results Change Between Sessions: The tool does not save data. Re-enter your values each session.

What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the calories your body burns at complete rest — just to keep organs functioning. TDEE (Total Daily Energy Expenditure) adds the calories burned through all physical activity. TDEE is the actual number you need to eat to maintain your current weight.

Why does gender affect the BMR calculation?

The Mifflin-St Jeor equation uses a different constant for males (+5) and females (−161) because males typically have higher lean muscle mass proportions at the same weight and height, resulting in a higher resting metabolic rate.

How fast should I expect to lose weight at a 500 kcal deficit?

Approximately 0.45 kg (1 lb) per week, since 3,500 kcal ≈ 0.45 kg of fat. Weight loss is rarely perfectly linear due to water retention, glycogen fluctuations, and hormonal factors.

Is my health data stored anywhere?

No. All calculations run client-side in your local browser. Your inputs are never uploaded.

• BMI Calculator: Calculate your Body Mass Index (BMI) instantly based on weight and height.
• BMR Calculator: Determine your Basal Metabolic Rate (BMR) using Mifflin-St Jeor formula.
• Water Intake Calculator: Calculate standard daily hydration requirements relative to weight and exercise load.
• Ideal Weight Calculator: Determine estimated ideal body weights based on Devine and Robinson equations.
• Body Fat Calculator: Estimate body fat percentage using US Navy circumference methodologies.
• Protein Intake Calculator: Calculate standard daily protein guidelines for body composition goals.

Mathematical Formula & Standards

This tool uses the Mifflin-St Jeor equation (validated in peer-reviewed research as the most accurate predictive equation for non-obese adults) to calculate Basal Metabolic Rate (BMR), then multiplies by an activity factor:

1. 1BMR Calculation (Mifflin-St Jeor):
2. 2Male: BMR = (10 * weight_{kg}) + (6.25 * height_{cm}) - (5 * age) + 5
3. 3Female: BMR = (10 * weight_{kg}) + (6.25 * height_{cm}) - (5 * age) - 161

1. 2Activity Multipliers (Harris–Benedict Scale):

1. 3TDEE Adjustment for Goals:
2. 2Fat loss: TDEE − 500 kcal/day (targets ~0.45 kg/week loss)
3. 3Muscle gain: TDEE + 250–500 kcal/day (lean bulk surplus)

[Age, Gender, Weight, Height, Activity Level]
                   |
                   v
[Mifflin-St Jeor BMR Equation]
                   |
                   v
[BMR × Activity Multiplier = TDEE]
                   |
                   v
[TDEE ± Goal Adjustment = Daily Calorie Target]

Result Interpretation Guidance

• Weight Loss (Female, 32 years): Weight 68 kg, Height 163 cm, Lightly Active. BMR = (680 + 1018.75 − 160 − 161) = 1,377.75 kcal. TDEE = 1,377.75 × 1.375 = 1,894 kcal. Fat loss target = 1,394 kcal/day.
• Muscle Gain (Male, 25 years): Weight 75 kg, Height 180 cm, Moderately Active. BMR = (750 + 1,125 − 125 + 5) = 1,755 kcal. TDEE = 1,755 × 1.55 = 2,720 kcal. Lean bulk target = 2,970–3,220 kcal/day.

• People Beginning a Weight Loss or Gain Program: Establishing a science-based calorie baseline before making dietary changes.
• Fitness Coaches: Providing clients with personalised TDEE estimates as part of a nutrition protocol.
• Endurance Athletes: Calculating energy intake requirements during high-volume training periods.
• Dietitians: Using as a rapid cross-check for manually derived calorie targets in initial client consultations.

• Before starting a structured diet to establish a calorie baseline rather than guessing.
• When changing activity levels (starting a new sport, recovering from injury) to recalibrate intake.
• To understand why your weight is not changing — if intake persistently matches TDEE, weight remains stable.

• Do not treat this as a clinical RMR measurement: TDEE from equations carries a ±10–15% margin of error for individuals. The only way to measure true resting metabolic rate precisely is indirect calorimetry in a clinical setting.
• Do not use this tool to restrict calories below 1,200 kcal/day (women) or 1,500 kcal/day (men) without medical supervision — very low calorie diets risk nutrient deficiencies and metabolic adaptation.
• Do not ignore hunger signals: Formula outputs are estimates. If you feel severely fatigued on the calculated deficit, the estimate may not match your actual metabolic rate.

Regulatory & Professional Disclaimer