Free Calorie Calculator Online

How to calculate calories: the formula explained

Calculating daily calorie needs starts with your Basal Metabolic Rate (BMR), the calories your body burns at complete rest. The Mifflin-St Jeor formula gives the most accurate BMR estimate for most adults. For men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5. For women: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161. Your BMR is then multiplied by an activity factor to get your TDEE (Total Daily Energy Expenditure), which is your true maintenance calorie level.

Activity multipliers range from 1.2 for a sedentary lifestyle with little movement to 1.9 for an extremely active person with a physical job and daily intense training. Your daily calorie requirement is the product of these two values. The calorie needs calculator on this page handles the full calculation instantly, returning your BMR, TDEE, and ready-to-use targets for every goal.

How to use the calorie calculator online

1. Enter your age, sex, height, and current body weight.
2. Select your daily activity level from sedentary to extra active.
3. Choose your goal: weight loss (deficit), maintenance, or muscle gain (surplus).
4. Read your BMR, maintenance calories (TDEE), and daily calorie target instantly.
5. Use the result as your daily nutrition budget, then track food intake against it.

Calorie deficit calculator: how many calories to eat for weight loss

A calorie deficit occurs when you eat fewer calories than your body burns. This is the only mechanism through which fat loss happens. The calorie deficit calculator on this page computes the exact deficit needed based on your personal TDEE. A deficit of 500 calories per day below your maintenance level produces approximately 0.45 kg (1 lb) of fat loss per week, since one pound of fat stores roughly 3,500 calories. A 250-calorie daily deficit gives slower, easier-to-sustain loss; a 750-calorie deficit gives faster results but requires more dietary discipline.

The most important rule for weight loss calorie targets: never eat below your minimum safe calorie floor. For most women this is 1,200 kcal per day; for most men it is 1,500 kcal per day. Below these levels, it becomes difficult to meet protein, vitamin, and mineral needs from food alone, and the risk of lean muscle loss rises significantly. Once you have your calorie target, pair it with the macro calculator to set your protein, carbohydrate, and fat targets, since a high-protein intake preserves muscle during a calorie deficit.

Maintenance calorie calculator: finding your baseline

Your maintenance calories, also called TDEE, are the number of calories that keep your body weight stable. Knowing this number is essential whether you want to lose fat, build muscle, or simply eat in a way that sustains your current weight. The maintenance calorie calculator uses your personal data and activity level to estimate this baseline. Eating at maintenance means no intentional weight change; it is the reference point from which all deficit or surplus targets are built.

For the most accurate maintenance calorie figure, track your body weight and actual calorie intake for two to four weeks without changing anything. If your weight stays constant, your average daily intake equals your true maintenance. The formula-based estimate from this calculator is a reliable starting point, but individual metabolic variation means the real number may be 5 to 15 percent higher or lower. For a deeper analysis of your energy expenditure, use the TDEE calculator, which also shows your BMR broken out separately.

Calorie surplus calculator: calories to gain weight and build muscle

If your goal is to gain weight or build muscle, you need a calorie surplus, eating more than your TDEE. A lean bulk typically uses a surplus of 100 to 250 calories per day above maintenance, which minimises fat gain while providing enough energy for muscle protein synthesis. A more aggressive bulk uses 300 to 500 calories above TDEE and produces faster weight gain but with a higher ratio of fat to muscle. The calorie calculator to gain weight shows these surplus targets directly in the results panel.

Gaining weight without enough protein undermines muscle growth even when the calorie surplus is adequate. Most research supports a target of 1.6 to 2.2 grams of protein per kilogram of body weight per day during a muscle-building phase. After calculating your calories to gain weight here, use the macro calculator to set a specific protein target and split the remaining calories between carbohydrates and fat.

Calories burned through exercise and daily activity

Your activity level multiplier already accounts for exercise calories in your TDEE calculation. As a guide to the magnitude of exercise calorie burn: a 70 kg person burns approximately 280 to 350 calories per hour walking at a moderate pace (5 km/h), making a walking calorie calculator estimate straightforward. Running at 10 km/h burns roughly 600 to 700 calories per hour for the same person. Cycling at moderate intensity burns 400 to 500 calories per hour, and strength training burns 200 to 300 calories per hour depending on intensity and rest periods.

Heavier individuals burn more calories for any given activity because more mass requires more energy to move. Conversely, as you lose weight through a calorie deficit, the same exercise burns fewer calories than before. This is one reason why recalculating your calorie needs every four to six weeks is important: both your resting calorie burn and your exercise calorie burn decrease as your body weight falls. If your current BMI puts you in the obese range, a moderate calorie deficit combined with regular low-impact exercise such as walking is the evidence-based starting point recommended by most clinical guidelines.

Daily calorie calculator for men vs women

Men and women have different daily calorie requirements even at the same body weight, height, and activity level. The key reason is body composition: men typically carry more skeletal muscle, which burns more calories at rest than fat tissue. The Mifflin-St Jeor formula reflects this with sex-specific constants that typically produce a 100 to 250 calorie per day difference in BMR. As a result, the daily calorie calculator for women will return a lower maintenance and deficit target than the same calculator used by a man of identical size and activity.

Women also experience hormonal fluctuations across the menstrual cycle that cause natural variation in appetite and energy expenditure of around 100 to 300 calories per day. A single daily calorie estimate does not capture this variation, but it remains the most practical starting point. For a sex-specific breakdown of your body composition alongside your calorie needs, pair this calculator with the body fat percentage calculator.