Calorie Calculator
Estimate your daily calorie needs for weight maintenance, loss, or gain using the Mifflin-St Jeor equation.
5'9" = 69 inches
BMR
—
Basal Metabolic Rate
Maintenance
—
Daily calories (TDEE)
Weight Loss
—
Lose ~1 lb/week
Weight Gain
—
Gain ~1 lb/week
What is TDEE?
Total Daily Energy Expenditure (TDEE) is the total number of calories you burn in a day, including your basal metabolism, physical activity, and the energy used to digest food. Understanding your TDEE is the foundation for any nutrition plan.
Calorie Deficit and Surplus
- Weight loss: Eat fewer calories than your TDEE. A 500-calorie daily deficit leads to roughly 1 pound of fat loss per week.
- Weight gain: Eat more calories than your TDEE. A 500-calorie daily surplus supports about 1 pound of weight gain per week.
- Maintenance: Eat approximately your TDEE to maintain your current weight.
Why 500 Calories ≈ 1 lb/Week
One pound of body fat stores approximately 3,500 calories. A deficit of 500 calories per day over 7 days totals 3,500 calories, resulting in roughly one pound of fat loss. This is an approximation, as metabolism adapts over time.
Macronutrient Balance
A common balanced split for general health is:
- Protein: 30% of calories (supports muscle maintenance)
- Carbohydrates: 40% of calories (primary energy source)
- Fat: 30% of calories (hormones and nutrient absorption)
When to Use This Calculator
- Starting a diet: Find your maintenance calories before creating a deficit to avoid under-eating.
- Weight loss plateau: Re-calculate after losing 10+ lbs, since your TDEE changes as your weight changes.
- Muscle building: Determine the right surplus before a bulking phase — 200-300 calories over TDEE minimizes fat gain.
Real-World Examples
Example 1 — Weight loss: 35-year-old male, 5'9", 195 lbs, moderately active. TDEE ≈ 2,700 cal. Loss target: 2,200 cal/day. Expected rate: 1 lb/week. Adjust after 4-6 weeks based on actual results.
Example 2 — Maintenance after goal: 28-year-old female, 5'5", 135 lbs, lightly active. TDEE ≈ 1,820 cal. She can eat 1,750-1,900 cal/day and expect stable weight.
Limitations & Assumptions
- Accuracy is typically ±10% — individual metabolism varies due to genetics, hormones, and gut microbiome.
- The Mifflin-St Jeor formula is validated for adults 18-65 with average body composition.
- Activity multipliers are approximations — fitness trackers often overestimate calorie burn by 15-30%.
- Does not account for adaptive thermogenesis — metabolism slows during prolonged caloric restriction.
Data Sources
BMR formula: Mifflin-St Jeor equation (1990), validated in Frankenfield et al. (2005) as the most accurate for non-obese individuals. Activity multipliers from the Harris-Benedict revision (Roza & Shizgal, 1984). Deficit/surplus relationship per National Institutes of Health (NIH) guidelines.
Related Data
Track calories and nutrition facts for 2M+ foods at GetFoodFacts. Explore vitamin and supplement data at PlainVitamins.
Disclaimer: This calculator provides estimates for informational purposes only. Consult your healthcare provider for medical advice.
Frequently Asked Questions
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