Calorie Calculator

This calculator relies on the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR)—the number of calories your body burns at complete rest. For biological males, the formula is BMR = 10 * weight (kg) + 6.25 * height (cm) - 5 * age (years) + 5. For biological females, it is BMR = 10 * weight (kg) + 6.25 * height (cm) - 5 * age (years) - 161. Once your BMR is established, it is multiplied by an activity factor ranging from 1.2 (sedentary) to 1.9 (extra active) to find your Total Daily Energy Expenditure (TDEE). Finally, macronutrients for carbohydrates, fats, and proteins are derived from your total calorie target to ensure balanced nutrition.

Let us walk through a practical example for a 30-year-old male who weighs 80 kg (176 lbs), stands 180 cm (5 ft 11 in) tall, and exercises moderately three to five days a week (activity factor of 1.55). First, we calculate his BMR: (10 * 80) + (6.25 * 180) - (5 * 30) + 5 = 800 + 1125 - 150 + 5 = 1,780 calories per day. Next, we multiply this BMR by his activity factor: 1,780 * 1.55 = 2,759 calories. This resulting 2,759 calories represents his maintenance level, which serves as the precise starting point for adjusting his diet toward weight loss or muscle gain.

Tracking your daily energy intake is a powerful habit, but accuracy matters. First, invest in a digital food scale to weigh your food in grams rather than relying on volume cups, which can lead to underreporting calories by up to 30%. Second, remember that activity factors can fluctuate; if your weight stalls for two weeks while trying to lose weight, adjust your activity tier downward or increase your daily step count. Finally, prioritize protein intake within your calorie budget to preserve lean muscle mass during weight loss phases.