ToolNix.io
Calorie Calculator
Calculate your daily calorie needs for weight loss, maintenance & muscle gain using the Mifflin-St Jeor formula.
Your Details
🇺🇸 Imperial (lbs / ft)
🌍 Metric (kg / cm)
👨 Male
👩 Female
Your Maintenance Calories (TDEE)
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calories / day · BMR: -- cal
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Lose 2 lbs/wk
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Lose 1 lb/wk
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Maintain Weight
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Gain 1 lb/wk
Calories by Activity Level
| Activity Level | Calories/Day |
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🔥 About This Calculator
Our free Calorie Calculator helps you find your personalized daily calorie needs based on your age, sex, height, weight, and activity level. Using the scientifically validated Mifflin-St Jeor equation, it calculates your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) — the two numbers that determine whether you lose, maintain, or gain weight.
Whether your goal is weight loss, muscle gain, or simply maintaining a healthy weight, this calculator gives you an accurate daily calorie target and a breakdown of recommended macronutrients — protein, carbohydrates, and fats.
📋 How to Use the Calorie Calculator
1
Enter your age and sex — Age and biological sex affect your metabolic rate and calorie needs significantly.
2
Input your height and weight — Choose metric (cm, kg) or imperial (ft/in, lbs) units. Your current weight, not goal weight.
3
Select your activity level — Be honest about your actual weekly exercise frequency. Overestimating activity is the most common mistake.
4
Choose your goal — Select weight loss, maintenance, or muscle gain. The calculator adjusts your target calories accordingly.
5
Review your results — See your BMR, TDEE, daily calorie target, and macronutrient recommendations for protein, carbs, and fats.
❓ Frequently Asked Questions
To lose 1 pound per week, you need a daily calorie deficit of approximately 500 calories below your TDEE. To lose 2 pounds per week, a 1,000 calorie deficit is needed. Never eat below 1,200 calories per day (women) or 1,500 calories per day (men) without medical supervision, as this can slow metabolism and cause muscle loss.
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest — just to keep your organs functioning. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor, representing total calories burned in a day including exercise and daily movement. TDEE is the number you should use for diet planning.
Our calculator uses the Mifflin-St Jeor equation, which research shows is accurate within 10% for most people. However, individual metabolism varies due to genetics, gut microbiome, hormones, and other factors. Treat the result as a solid starting point, then adjust by 100-200 calories after 2-3 weeks based on your actual weight change.
Calorie counting is not mandatory but is highly effective for creating awareness. Studies show most people underestimate their food intake by 20-40%. Even tracking for 4 to 8 weeks can teach you portion sizes and food awareness that lasts long-term. Many people maintain results intuitively after an initial tracking period.
Calorie burn during exercise varies by type, intensity, body weight, and fitness level. Approximate burns per 30 minutes: walking (150 cal), jogging (300 cal), cycling (250 cal), swimming (200 cal), strength training (180 cal). Our calculator accounts for your overall activity level rather than individual exercise sessions.