How Many Calories Should I Eat Per Day? Calculate Your TDEE (2026)
"Eat 2,000 calories a day" — that's the FDA's one-size-fits-all answer, and it's technically for a 2,000-calorie reference diet used on nutrition labels, not a personalized recommendation. Your actual number could be anywhere from 1,400 to 3,500+ depending on who you are and what you do with your day. The only way to get a useful number is to calculate it from your own stats. It takes about two minutes.
The Two Numbers You Need: BMR and TDEE
BMR (Basal Metabolic Rate) is the number of calories your body needs to stay alive at complete rest — breathing, circulating blood, maintaining organ function, and body temperature. If you stayed in bed all day without moving, this is what you'd burn.
TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor, representing the total calories you actually burn in a day including all movement and exercise. TDEE is the number you should base eating decisions on.
The Mifflin-St Jeor Equation
Published in 1990, the Mifflin-St Jeor equation is currently considered the most accurate BMR formula for most people — more accurate than the older Harris-Benedict equation, which has been shown to overestimate by 5–15%.
Activity Multipliers: From BMR to TDEE
Once you have your BMR, multiply by the factor that best describes your typical week:
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, little or no exercise |
| Lightly active | 1.375 | Light exercise 1–3 days/week |
| Moderately active | 1.55 | Moderate exercise 3–5 days/week |
| Very active | 1.725 | Hard exercise 6–7 days/week |
| Extra active | 1.9 | Physical job + daily intense exercise |
Using the example above (BMR 1,699) with moderate activity: TDEE = 1,699 × 1.55 = 2,633 kcal/day. That's the maintenance level — eat this, and weight stays roughly stable over time.
Setting Your Calorie Target Based on Goals
For Weight Loss
A calorie deficit creates weight loss. The general rule is that 3,500 calories = approximately 1 lb of body fat. A daily deficit of 500 calories below TDEE should produce roughly 1 lb per week of fat loss — a rate considered sustainable and safe for most people.
- Moderate deficit (−500 kcal/day): ~1 lb/week loss — recommended for most people
- Aggressive deficit (−750 kcal/day): ~1.5 lbs/week — requires careful nutrient management
- Very aggressive (−1,000+ kcal/day): ~2 lbs/week — not recommended without medical supervision
Minimum calorie floors: Most health guidelines recommend not going below 1,200 kcal/day for women or 1,500 kcal/day for men without medical supervision. Very-low-calorie diets risk muscle loss, nutritional deficiencies, and metabolic adaptation.
For Weight Gain (Lean Muscle)
Building muscle requires a caloric surplus — eating more than you burn. A modest surplus of 250–300 calories above TDEE supports lean muscle gain when combined with resistance training, while minimising excess fat accumulation. Larger surpluses ("bulking") add mass faster but also more fat.
For Maintenance
Eat at your TDEE. In practice, this means targeting a range (±100–150 calories) rather than a precise number, since calorie counts in food are estimates and daily activity varies.
The Macro Breakdown: Protein, Carbs, and Fats
Once you have your calorie target, distributing those calories across macronutrients matters for body composition and performance:
| Macro | Calories per gram | General recommendation | Example at 2,500 kcal |
|---|---|---|---|
| Protein | 4 kcal/g | 25–35% of calories | 156–219g |
| Carbohydrates | 4 kcal/g | 40–55% of calories | 250–344g |
| Fats | 9 kcal/g | 20–35% of calories | 56–97g |
Protein intake is particularly important when in a caloric deficit — higher protein (up to 1g per lb of bodyweight) helps preserve muscle mass while losing fat.
Why Calorie Calculators Don't All Agree
Different calculators use different equations (Harris-Benedict, Mifflin-St Jeor, Katch-McArdle), and different activity multipliers. The Mifflin-St Jeor equation is the current gold standard for most people, but it's still an estimate — individual metabolic rates can vary by 15–20% from predictions. Treat any calculator output as a starting point, then adjust based on your actual results over 2–4 weeks.
Calculate your personal daily calorie target in seconds.
Use the Free Calorie Calculator →Frequently Asked Questions
⚠️ Calorie estimates are for informational purposes only and not a substitute for personalised medical or dietetic advice. Individual needs vary. Consult a registered dietitian before making significant dietary changes.