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How many calories should I eat per day?

Calculate your daily calorie needs based on age, gender, weight, height, and activity level. Get personalized recommendations for weight loss, maintenance, or gain.

What This Calculator Is

A calorie calculator estimates your Total Daily Energy Expenditure (TDEE)—the calories you burn daily based on your body size, age, and activity level. It provides maintenance calories (to stay the same weight) plus targets for weight loss or muscle gain. This is the foundation of any nutrition plan.

Who This Calculator Is For

Anyone starting a diet or nutrition program, people wanting to understand their energy needs, athletes optimizing performance nutrition, and those who've struggled with weight and want a scientific starting point.

When to Use This Calculator

Use this calculator when starting a weight loss or gain program, when your activity level changes significantly, when tracking isn't producing expected results (you may need to recalculate), or when planning meal prep and portion sizes.

Inputs

30
170
5
10

Results

Maintenance Calories

2,693

Weight Loss (1 lb/week)2,193
Weight Gain (1 lb/week)3,193
Basal Metabolic Rate1,737

Results are general guidelines, not medical advice. Consult a healthcare provider.

Insights

Your daily energy needs

You need approximately 2,693 calories daily to maintain your current weight.

Adjust for goals

For weight loss, target 2,193 cal/day. For muscle gain, aim for 3,193 cal/day.

How Calorie Is Calculated

The calculator uses the Mifflin-St Jeor equation to calculate your Basal Metabolic Rate (BMR), then multiplies by an activity factor to estimate total daily calorie needs.

BMR (Mifflin-St Jeor): male = 10*weightKg + 6.25*heightCm - 5*age + 5; female = 10*weightKg + 6.25*heightCm - 5*age - 161
maintenanceCalories = BMR * activityMultiplier
weightLossCalories = maintenanceCalories - 500; weightGainCalories = maintenanceCalories + 500
Where:
activityMultiplier: sedentary=1.2, light=1.375, moderate=1.55, active=1.725, veryActive=1.9 (default 1.55 if unrecognized)
weightKg = weight(lbs)*0.453592; heightCm = (feet*12+inches)*2.54
Assumptions:
Mifflin-St Jeor equation (not Harris-Benedict)
Flat +/-500 kcal/day adjustment for loss/gain (~1 lb/week change assumption)
Results rounded to nearest whole calorie; NaN falls back to 2000/1500/2500/1500 defaults

Key Takeaways

  • •For safe weight loss, aim for a 500-calorie deficit (1 lb/week)
  • •Don't go below 1,200 calories (women) or 1,500 (men) without medical supervision
  • •Re-calculate every 10-15 lbs lost as your needs change
  • •Track actual results and adjust — calculators provide estimates
  • •Protein needs increase when in a calorie deficit to preserve muscle

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