Calorie Calculator
Estimate your daily calorie needs and weight-goal targets
Your Details
BMR (at rest)
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kcal/day
Maintenance (TDEE)
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kcal/day
Daily Calories by Goal
The Calorie Calculator estimates how many calories your body needs per day: your basal metabolic rate (BMR), your maintenance calories (TDEE), and five weight-goal targets from losing 0.5 kg per week to gaining 0.5 kg per week. Enter your age, sex, height, weight, and activity level — get your numbers in seconds.
How to Use
Fill in your stats and read your targets:
- Enter your details: age, sex, height (cm), and weight (kg)
- Pick an activity level: be honest — most people overestimate
- Click Calculate: see your BMR, maintenance TDEE, and goal calories
- Choose a goal card: from −0.5 kg/week up to +0.5 kg/week
Features
- BMR via the Mifflin-St Jeor equation (male/female variants)
- Five activity levels with standard multipliers from 1.2 to 1.9
- Five weight-goal targets: ±0.25 and ±0.5 kg per week (±250/500 kcal per day)
- 100% client-side — your body data never leaves the browser
How the Calculation Works
The Mifflin-St Jeor equation first estimates your basal metabolic rate — the calories you would burn lying in bed all day. Multiplying by an activity factor from 1.2 (sedentary) to 1.9 (very active) yields your TDEE, the intake that keeps your weight stable.
Each goal then shifts your TDEE: about 7700 kcal equals one kilogram of body fat, so a 500 kcal daily deficit works out to roughly half a kilogram lost per week, and a 250 kcal surplus to a quarter kilogram gained. Treat the numbers as a starting point and adjust based on real-world progress.
Use Cases
- Fat loss: pick a sustainable deficit of 250 or 500 kcal per day
- Muscle gain: size a modest surplus instead of guessing
- Maintenance: find the intake that keeps your weight stable
- Meal planning: turn your calorie target into macros and portions
Related Tools
Frequently Asked Questions
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest — just keeping your organs running. TDEE (Total Daily Energy Expenditure) multiplies your BMR by an activity factor (1.2 to 1.9) to account for exercise and daily movement. TDEE is your maintenance calories: eat that much and your weight stays stable.
Which equation does this calculator use?
It uses the Mifflin-St Jeor equation, considered the most accurate BMR formula for the general population: 10 × weight(kg) + 6.25 × height(cm) − 5 × age, plus 5 for men or minus 161 for women.
How accurate are the results?
The results are estimates, not medical advice. Individual metabolism, muscle mass, hormones, and genetics can shift your actual needs by 10-15% in either direction. Use the numbers as a starting point, track your weight for two to three weeks, and adjust from real-world results.
How fast can I safely lose or gain weight?
The ±500 kcal/day targets correspond to roughly 0.5 kg (about 1 lb) per week, and ±250 kcal/day to about 0.25 kg per week. Slower rates are generally easier to sustain and preserve more muscle when losing weight. Very aggressive deficits are not recommended without medical supervision.
How do I turn my calorie target into meals?
Once you know your daily calorie target, split it into protein, carbs, and fat with the Macro Calculator — it converts your calories into exact grams per macronutrient based on your goal.