Calorie Calculator
Calculate your daily calorie needs based on your goals and activity level.
Related Calculators
About This Calculator
"How many calories should I eat to lose weight?" It's the most searched nutrition question on the internet—and the answer is more complicated than "2,000 calories a day."
Here's what nutrition labels won't tell you: the "2,000 calorie diet" is a political compromise, not science. In 1990, the FDA needed a single number for food labels. Women's groups suggested 1,800 calories; industry wanted 2,500. They split the difference, rounded to 2,000, and printed it on every package in America. Your actual needs could be 1,400 or 3,500+ depending on your size, age, activity, and goals.
The average American now consumes approximately 3,600 calories per day—nearly double what many people need. Meanwhile, ultra-processed foods make up over 60% of the American diet. No wonder 70% of Americans are overweight or obese.
Understanding your true calorie needs is the foundation of any successful nutrition plan. Whether you want to lose fat, build muscle, or just stop gaining weight, it all starts with one number: your TDEE (Total Daily Energy Expenditure).
This calculator uses the Mifflin-St Jeor equation (1990), which studies show is the most accurate formula for modern populations. Unlike the outdated Harris-Benedict equation from 1919 that many calculators still use, Mifflin-St Jeor was developed on contemporary subjects and doesn't systematically overestimate your needs.
We'll show you your BMR (what you'd burn in a coma), your TDEE (what you actually burn each day), and customized calorie targets for any goal—whether that's finally losing those stubborn 20 pounds or fueling your muscle-building phase.
Disclaimer: These are estimates based on population averages. Individual metabolism varies due to genetics, hormones, and body composition. Track your weight for 2-3 weeks and adjust accordingly. Consult a healthcare provider before making significant dietary changes.
Trusted Sources
How to Use the Calorie Calculator
- 1**Enter your biological sex**: Men typically burn 5-10% more calories than women at the same size due to differences in muscle mass and hormones.
- 2**Enter your age accurately**: Metabolism decreases about 1-2% per decade after age 20. A 50-year-old burns fewer calories than a 25-year-old at the same size.
- 3**Enter your height and weight**: Use accurate, recent measurements. Weigh yourself in the morning, after using the bathroom, before eating.
- 4**Select your activity level honestly**: This is where most people go wrong. If you have a desk job and work out 3x/week, you're "Lightly Active"—not "Moderately Active." When in doubt, round down.
- 5**Choose your goal**: Select weight loss, maintenance, or muscle gain. The calculator adjusts your target calories based on safe, sustainable rates of change.
- 6**Review your results**: You'll see your BMR (basal metabolic rate), TDEE (total daily expenditure), and goal-specific calorie target.
- 7**Start tracking with a food scale**: What you think is "a cup" or "a tablespoon" is probably 20-50% more. Accuracy matters.
- 8**Reassess after 2-3 weeks**: If your weight isn't changing as expected, adjust by 100-200 calories. Your body is the ultimate arbiter.
The Science of Calorie Calculation
Your daily calorie needs come from two calculations:
Step 1: BMR (Basal Metabolic Rate)
BMR is what your body burns at complete rest—lying still, not moving, just keeping you alive. It covers:
- Breathing and heart function
- Brain activity (uses ~20% of BMR)
- Cell repair and regeneration
- Temperature regulation
The Mifflin-St Jeor Equations:
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161
Step 2: TDEE (Total Daily Energy Expenditure)
Multiply your BMR by an activity factor:
| Activity Level | Multiplier | Real-World Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, under 4,000 steps/day, no exercise |
| Lightly Active | 1.375 | Desk job + 1-3 light workouts/week OR 5,000-7,000 steps |
| Moderately Active | 1.55 | Active job OR desk job + 3-5 workouts + 7,000+ steps |
| Very Active | 1.725 | Physical job + regular exercise OR intense training 6-7x/week |
| Extremely Active | 1.9 | Professional athlete OR heavy manual labor + training |
Example Calculation
35-year-old woman, 160 lbs (73 kg), 5'6" (168 cm), desk job + gym 3x/week:
BMR = (10 × 73) + (6.25 × 168) - (5 × 35) - 161 = 1,449 calories TDEE = 1,449 × 1.375 = 1,992 calories/day
For 1 lb/week fat loss: 1,992 - 500 = 1,492 calories/day
Why Most Calorie Calculators Are Wrong
Many online calculators still use formulas that are over 100 years old:
Formula Accuracy Comparison
| Formula | Year Created | Sample Size | Accuracy | Problem |
|---|---|---|---|---|
| Harris-Benedict | 1919 | 239 | ±10-15% | Outdated population, overestimates |
| Revised Harris-Benedict | 1984 | 337 | ±7-10% | Still limited sample |
| Mifflin-St Jeor | 1990 | 498 | ±5% | Best for modern populations |
| Katch-McArdle | 1990 | N/A | ±5% | Requires body fat % measurement |
The Harris-Benedict Problem
The original Harris-Benedict equation was developed in a Boston lab on 239 well-fed volunteers—mostly white males in their 20s-30s. It consistently overestimates calorie needs by 5-15% because:
- Modern lifestyles are more sedentary
- Body compositions have changed
- Sample wasn't representative
If you've ever eaten at your "calculated" maintenance and gained weight, an outdated formula was likely the culprit.
The Activity Level Problem
Research shows people overestimate their activity level by one full category on average.
Common mistakes:
- "I go to the gym 3x/week" → Still sedentary if you sit 10+ hours otherwise
- "I have an active job" → Nurses/servers are moderately active, not very active
- "I walk a lot" → Track actual steps; most people overestimate by 50%
Rule of thumb: When in doubt, select one level LOWER than you think.
Calorie Targets by Goal: The Math That Actually Works
Once you know your TDEE, adjust based on your goal:
Fat Loss: Creating a Deficit
| Daily Deficit | Weekly Fat Loss | Muscle Preservation | Sustainability |
|---|---|---|---|
| -250 calories | ~0.5 lb/week | Excellent | Very High |
| -500 calories | ~1 lb/week | Good | Good (recommended) |
| -750 calories | ~1.5 lb/week | Moderate | Moderate |
| -1000 calories | ~2 lb/week | Poor | Low (short-term only) |
Critical Minimums:
- Women: Never below 1,200 calories
- Men: Never below 1,500 calories
Going lower risks muscle loss, nutrient deficiencies, metabolic slowdown, hormonal disruption, and binge triggers.
Weight Maintenance
- Start eating at your calculated TDEE
- Track weight for 2-3 weeks (weigh daily, average weekly)
- Adjust by ±100 calories if trending up or down
- Expect daily fluctuations of 2-5 lbs from water, food weight, and waste
Muscle Gain (Bulking)
| Daily Surplus | Weekly Gain | Fat Gain Risk | Best For |
|---|---|---|---|
| +200-300 cal | ~0.5 lb/week | Low | Lean bulk, experienced lifters |
| +500 cal | ~1 lb/week | Moderate | Standard bulk, beginners |
Reality check: Natural lifters can only build 0.25-0.5 lb of actual muscle per week at best. Larger surpluses mostly add fat.
Example Targets (2,000 TDEE)
| Goal | Daily Calories | Expected Result |
|---|---|---|
| Aggressive cut | 1,000 | -2 lb/week (not recommended long-term) |
| Moderate cut | 1,500 | -1 lb/week |
| Slight cut | 1,750 | -0.5 lb/week |
| Maintenance | 2,000 | Weight stable |
| Lean bulk | 2,300 | +0.5 lb/week |
Macronutrients: Where Your Calories Come From Matters
Calories control weight, but macros control body composition:
Protein: The King of Macros (4 calories per gram)
| Goal | Protein Target | For 150 lb Person |
|---|---|---|
| Sedentary adult (RDA) | 0.8 g/kg (minimum) | 54g/day |
| General fitness | 1.2-1.4 g/kg | 82-95g/day |
| Building muscle | 1.6-2.2 g/kg | 109-150g/day |
| Dieting (preserve muscle) | 1.8-2.4 g/kg | 123-163g/day |
Why high protein matters:
- Most satiating macro (keeps you full longer)
- Highest thermic effect (burns 20-30% of its calories during digestion)
- Preserves muscle during fat loss
- Required for muscle building
Carbohydrates (4 calories per gram)
| Approach | Carb Intake | Best For |
|---|---|---|
| High carb | 45-65% of calories | Athletes, high activity |
| Moderate carb | 30-45% of calories | General population |
| Low carb | 20-30% of calories | Sedentary, fat loss focus |
| Keto | <50g/day | Specific medical/preference |
Carbs aren't evil—they fuel workouts and brain function. But sedentary people need fewer than athletes.
Fat (9 calories per gram)
| Guideline | Amount |
|---|---|
| Minimum for hormones | 0.3g per lb bodyweight |
| Standard recommendation | 25-35% of calories |
| Low-fat (not recommended) | <20% of calories |
Fat is essential for hormone production, vitamin absorption, and brain function. Don't go too low.
Sample Day: 1,800 Calories
| Macro | % of Calories | Grams | Calories |
|---|---|---|---|
| Protein | 30% | 135g | 540 |
| Carbs | 40% | 180g | 720 |
| Fat | 30% | 60g | 540 |
The Metabolism Reality: What Actually Affects Your Calorie Burn
Your metabolism isn't fixed—it's influenced by many factors:
Factors You Can't Control
| Factor | Impact on Calorie Needs |
|---|---|
| Age | -1-2% per decade after 20 |
| Biological sex | Men burn ~5-10% more |
| Genetics | Can vary metabolism by 200-500 cal/day |
| Height | Taller = higher BMR |
Factors You CAN Control
| Factor | Impact |
|---|---|
| Muscle mass | Each lb of muscle burns ~6 cal/day at rest |
| Activity level | Can add 500-1,500+ calories to daily burn |
| NEAT | Fidgeting, walking, standing can burn 200-500+ cal/day |
| Sleep | Poor sleep can decrease metabolism 2-8% |
| Crash dieting | Can reduce metabolism 10-15% temporarily |
The Metabolic Adaptation Problem
When you diet, your body adapts:
- Thyroid hormone decreases
- NEAT (fidgeting, movement) decreases unconsciously
- Hunger hormones increase
- Energy levels drop
This can reduce your calorie burn by 10-15% beyond what weight loss alone would predict.
The fix:
- Don't crash diet (keep deficit moderate)
- Take diet breaks (1-2 weeks at maintenance every 8-12 weeks)
- Maintain/build muscle through resistance training
- Keep activity high (steps, walking)
The Thermic Effect of Food (TEF)
You burn calories digesting food:
| Macronutrient | Thermic Effect |
|---|---|
| Protein | 20-35% of calories |
| Carbs | 5-15% of calories |
| Fat | 0-5% of calories |
This is why high-protein diets are effective—you literally burn more calories processing protein.
Tracking Calories: The Skills That Make or Break Your Success
Knowing your calorie target is only half the battle. Accurate tracking is what makes it work.
The Tracking Problem
Studies consistently show people underestimate calorie intake by 30-50%:
- A "tablespoon" of peanut butter is often 2-3 tablespoons
- A "cup" of cereal is often 1.5-2 cups
- Cooking oils are frequently untracked (1 tbsp = 120 cal)
- Drinks, sauces, and "just a bite" add up
How to Track Accurately
1. Use a Food Scale
Weighing food is 10x more accurate than measuring cups:
- Cups can vary by 20-50% depending on how packed
- Serving sizes on labels are weights, not volumes
- A $15 food scale changes everything
2. Track BEFORE You Eat
Log food before eating, not after. This:
- Prevents "forgetting" to track snacks
- Helps you make better decisions
- Creates awareness of portion sizes
3. Track Everything
The things people don't track:
- Cooking oils and butter (120 cal per tbsp)
- Coffee creamers and lattes (50-300 cal)
- Condiments and sauces (50-200 cal)
- "Just a taste" while cooking (100-300 cal)
- Weekend alcohol (500-1,500+ cal)
4. Be Honest About Weekends
Monday-Friday discipline can be erased by weekend overeating:
| Weekday Deficit | Weekend Surplus | Net Weekly Result |
|---|---|---|
| -500 cal × 5 days = -2,500 | +1,500 cal × 2 days = +3,000 | +500 cal (gaining!) |
Two "cheat days" can literally eliminate a week's progress.
Recommended Tracking Apps
| App | Pros | Cons |
|---|---|---|
| MyFitnessPal | Large food database | Lots of user-entered errors |
| Cronometer | Most accurate database | Smaller database |
| Lose It! | User-friendly | Some database errors |
| MacroFactor | Adaptive (adjusts targets) | Subscription required |
Common Calorie Mistakes (And How to Fix Them)
After working with thousands of people tracking calories, these are the most common mistakes:
Mistake #1: Eating Back Exercise Calories
The problem: Exercise calorie estimates are wildly inaccurate—typically overestimated by 30-50%.
| Device Says | Reality |
|---|---|
| Treadmill: 500 cal | Actual: 300-350 cal |
| Apple Watch: 400 cal | Actual: 250-350 cal |
| Gym machine: 600 cal | Actual: 350-450 cal |
The fix: Don't "eat back" exercise calories. Your activity multiplier already accounts for exercise. If you must, only eat back 50% maximum.
Mistake #2: Liquid Calories
Drinks people forget to track:
| Drink | Calories | Frequency Impact |
|---|---|---|
| Starbucks latte (grande) | 190 | Daily = 1,330/week |
| Orange juice (12 oz) | 168 | Daily = 1,176/week |
| 2 glasses wine | 250 | 3x/week = 750/week |
| Beer (2 pints) | 400 | Weekend = 800/week |
| Smoothie | 300-600 | Daily = 2,100-4,200/week |
A daily Starbucks habit alone can prevent fat loss even in a "deficit."
Mistake #3: Underestimating Oils and Fats
| Item | What People Think | Reality |
|---|---|---|
| "A little olive oil" | 50 cal | 200-400 cal |
| "Light butter on toast" | 30 cal | 100+ cal |
| Salad dressing (2 tbsp) | 50 cal | 140-200 cal |
| Mayo (1 tbsp) | 50 cal | 94 cal |
Cooking oils are the #1 hidden calorie source.
Mistake #4: Restaurant Meals
Restaurant portions are typically 2-3x home portions:
| Menu Item | Listed Calories | Actual Calories |
|---|---|---|
| "Grilled chicken salad" | 450 | 800-1,200 |
| Pasta dish | 600 | 1,200-1,800 |
| Burger and fries | 900 | 1,400-2,000 |
When eating out: assume 25-50% more calories than listed, or just accept it as a maintenance/surplus day.
Pro Tips
- 💡Use a food scale—studies show people underestimate portions by 30-50% when eyeballing. A $15 scale is the best investment for accurate tracking.
- 💡Log food BEFORE you eat it, not after. This prevents "forgetting" to track snacks and helps you make better decisions in the moment.
- 💡Front-load protein at breakfast—it reduces hunger and cravings throughout the day and sets a satiety foundation.
- 💡Track cooking oils meticulously—1 tablespoon is 120 calories, and most people use 2-3 tablespoons without realizing.
- 💡Weigh yourself daily at the same time (morning, after bathroom, before food), but only compare weekly averages. Daily weight fluctuates 2-5 lbs.
- 💡When eating out, assume 25-50% more calories than listed. Restaurant nutrition info is often based on ideal portions, not actual servings.
- 💡Reassess your calorie target after every 10-15 lbs of weight change—your needs decrease as you get smaller.
- 💡If weight loss stalls for 3+ weeks, take a 1-2 week "diet break" at maintenance calories to reset hormones and metabolism.
- 💡Focus on weekly calorie averages, not daily perfection. One 500-calorie over-day is easily balanced by a 500-calorie under-day.
- 💡Prioritize sleep—poor sleep increases hunger hormones by 20-25%, decreases willpower, and makes sticking to calories much harder.
- 💡Eat whole foods over processed—100 calories of chicken keeps you fuller than 100 calories of chips, making the deficit easier to maintain.
- 💡Be especially careful with liquid calories—lattes, smoothies, juices, and alcohol can add 300-1,000+ untracked calories per day.
Frequently Asked Questions
To lose weight, eat 500-750 calories below your TDEE (Total Daily Energy Expenditure) for 1-1.5 lbs of fat loss per week. Calculate your TDEE first, then subtract. For most women, this means 1,200-1,600 calories; for most men, 1,500-2,000 calories. Never go below 1,200 (women) or 1,500 (men) without medical supervision.
