How this calorie calculator works
This calculator estimates BMR (basal metabolic rate) using one of three validated equations, then multiplies by an activity factor to estimate TDEE (total daily energy expenditure). Mifflin–St Jeor is the default and is considered very accurate for most people. Revised Harris–Benedict is an older alternative. Katch–McArdle uses body fat percentage and lean mass and can be preferable when you have a reliable body-fat estimate, especially if you are lean and muscular.
Mifflin–St Jeor (default)
W = weight (kg), H = height (cm), A = age (years).
- Men: BMR = 10W + 6.25H − 5A + 5
- Women: BMR = 10W + 6.25H − 5A − 161
Revised Harris–Benedict
- Men: BMR = 13.397W + 4.799H − 5.677A + 88.362
- Women: BMR = 9.247W + 3.098H − 4.330A + 447.593
Katch–McArdle
BMR = 370 + 21.6 × (1 − F) × W, where F is body fat as a decimal (e.g. 18% → 0.18) and W is kg. Gender is not used in this formula.
Activity level multipliers
TDEE = BMR × multiplier. Your maintenance calories are approximately your TDEE if your routine stays similar.
| Activity level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Little or no exercise, desk job |
| 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 | Very hard exercise, physical job, or 2× training |
- Exercise: about 15–30 minutes of elevated heart rate.
- Intense exercise: about 45–120 minutes of elevated heart rate.
- Very intense exercise: about 2+ hours of elevated heart rate.
How many calories do you need per day?
Needs vary with size, age, sex, and activity. As a very broad reference, the U.S. Department of Health has cited ranges such as roughly 2,000–3,000 kcal/day for adult men and 1,600–2,400 kcal/day for adult women to maintain weight — your personal number may sit well outside those averages. Harvard Health has suggested at least about 1,200 kcal per day for women and 1,500 kcal for men unless a clinician supervises lower intakes.
Calorie goals for weight loss
About 3,500 kcal is often used as a rough rule-of-thumb for one pound of fat. That implies about a 500 kcal/day deficit for ~1 lb/week — a common starting point, not a guarantee.
| Goal | Daily deficit (typical) | Rough pace |
|---|---|---|
| Slower loss | ~250 kcal | ~½ lb/week |
| Moderate loss | ~500 kcal | ~1 lb/week |
| Aggressive loss | ~750 kcal | ~1½ lb/week |
| Maximum often cited without supervision | ~1000 kcal | ~2 lb/week |
Deficits larger than about 1,000 kcal/day are often discouraged without medical oversight: faster loss can mean more muscle loss, lower metabolic rate, dehydration swings, nutrient gaps, and higher regain risk.
Calorie goals for weight gain
Adding about 250–500 kcal above TDEE, with resistance training, is a common frame for lean gain. Surplus without training stimulus mostly favors fat gain.
Calorie counting — practical steps
- Estimate TDEE (calculator above).
- Set a target (e.g. TDEE − 500 for moderate loss).
- Track intake with an app, spreadsheet, or journal — consistency beats perfection.
- Weigh under similar conditions and use weekly averages.
- Adjust based on real-world trend; equations are starting points.
Labels and databases can be wrong; digestion and preparation vary. Calorie awareness still helps many people with portions and food choices even if they do not track forever.
Zigzag calorie cycling
Alternating higher- and lower-calorie days while hitting the same weekly total can add flexibility (weekends, social meals) and is one approach some use when progress stalls — evidence is mixed and patterns are personal. The calculator shows an example pattern (two maintenance days + five lower days) that matches the same weekly average as a steady ~500 kcal deficit.
Food quality — not just quantity
Energy balance drives weight change, but protein, fiber, and whole foods usually improve satiety and nutrition. Protein has a higher thermic effect than fat or carbohydrate. Liquid calories and ultra-processed foods often make deficits harder. Drinks can add a large share of intake — water, tea, and black coffee are lower-calorie options.
Calories in common foods
Approximate values for planning; brands and portions vary.
| Food | Serving | kcal |
|---|---|---|
| Apple | 1 medium (4 oz) | 59 |
| Banana | 1 medium (6 oz) | 151 |
| Orange | 1 medium (4 oz) | 53 |
| Strawberries | 1 cup | 53 |
| Broccoli | 1 cup | 45 |
| Carrots | 1 cup | 50 |
| Chicken, cooked | 2 oz | 136 |
| Egg | 1 large | 78 |
| White bread | 1 slice | 75 |
| Rice, cooked | 1 cup | 206 |
| Pizza | 1 slice (14") | 285 |
| Beer | 1 can | 154 |
| Coca-Cola Classic | 1 can | 150 |
| Whole milk | 1 cup | 146 |
Calories burned — common exercises (per hour)
Approximate; intensity and body composition matter.
| Activity (1 hr) | 125 lb | 155 lb | 185 lb |
|---|---|---|---|
| Walking (3.5 mph) | 215 | 267 | 319 |
| Golf (cart) | 198 | 246 | 294 |
| Swimming (moderate) | 397 | 492 | 587 |
| Cycling (12–14 mph) | 454 | 562 | 671 |
| Tennis | 397 | 492 | 587 |
| Basketball | 340 | 422 | 503 |
| Soccer | 397 | 492 | 587 |
| Running (9 min/mile) | 624 | 773 | 923 |
Energy from macronutrients
| Component | kcal/g (approx.) |
|---|---|
| Fat | 8.8 |
| Protein | 4.1 |
| Carbohydrate | 4.1 |
| Fiber | 1.9 |
| Alcohol (ethanol) | 6.9 |
Published values vary slightly (e.g. Atwater 4/4/9 on labels vs. more precise experimental averages). Alcohol calories add up quickly.
Sample daily meal plans
Illustrative ideas only — adjust to your culture, preferences, and nutrition needs.
- ~1,200 kcal plan: breakfast: cereal + milk + banana; snacks: cucumber + dip, walnuts + apple; lunch: grilled cheese + salad; dinner: chicken + Brussels sprouts + quinoa.
- ~1,500 kcal plan: breakfast: granola + yogurt + berries; snacks: orange + yogurt; lunch: soup + bread; snack: peanut butter + apple; dinner: steak + potatoes + asparagus.
- ~2,000 kcal plan: breakfast: toast + egg + banana + almonds; snack: hummus + carrots + crackers; lunch: chicken + vegetables + pasta; snack: walnuts; dinner: salmon + brown rice + green beans.
For BMI and weight categories, use the BMI Calculator.