Bulk/Cut Calorie Calculator

Most lifters do better with moderate, consistent deficits rather than aggressive cuts that risk muscle loss and energy crashes. Deficits larger than 700-800 kcal/day are associated with greater lean mass loss, especially without adequate protein intake and resistance training. A 300-500 kcal/day deficit is a practical starting range for most people — at 500 kcal below maintenance, the theoretical rate of fat loss is roughly 0.5 kg per week. Aggressive deficits may be appropriate in specific short-term contexts, but are generally harder to sustain and should be approached carefully.

No. This calculator is an educational planning support tool only and does not constitute medical or dietetic advice. Individual calorie needs vary significantly based on health status, medications, metabolic conditions, and activity levels. If you have a diagnosed health condition, are pregnant, or have a history of disordered eating, consult a registered dietitian or qualified health professional before making significant dietary changes.

A lean bulk typically uses a surplus of 200-500 kcal/day above maintenance, which supports muscle gain while limiting excess fat accumulation. At 200-250 kcal above maintenance, weight gain will be slow — roughly 0.1-0.2 kg per week — but the gain is more likely to be lean mass. Larger surpluses above 500 kcal/day tend to accelerate fat storage without proportionally accelerating muscle growth for most natural lifters. For example, if your maintenance is 2,600 kcal, a lean bulk target of 2,800-2,900 kcal is a sensible starting point.

A deficit of 300-500 kcal/day is widely recommended as a muscle-preserving range for most lifters. At this level, fat loss proceeds at approximately 0.3-0.5 kg per week, which is sustainable and allows adequate protein and energy for training performance. Larger deficits can cause faster weight loss but increase the risk of muscle catabolism, strength decline, and hormonal disruption over time. Keeping protein intake at or above 1.6-2.2 g per kg of body weight is critical for retaining lean mass during a cut.

The most reliable method is to track your food intake consistently for 2-3 weeks while keeping body weight stable — the average daily intake during that period is your practical maintenance. Alternatively, use a Total Daily Energy Expenditure (TDEE) formula such as the Mifflin-St Jeor equation adjusted for your activity level as a starting estimate. TDEE formulas are a reasonable starting point but can be off by 200-400 kcal for some individuals, so real-world tracking is more accurate. Once you have a maintenance estimate, monitor weekly weight trends to validate and adjust it.

Review your average daily weight over 2-3 weeks rather than reacting to single daily weigh-ins, since water, sodium, and glycogen fluctuations can shift scale weight by 1-2 kg overnight. If you are in a surplus and gaining faster than 0.25-0.5 kg per week, reduce your delta by 100-200 kcal. If you are in a deficit and not losing weight after two consistent weeks, reduce your target by 100-200 kcal or increase activity. Adjustments should be incremental — large swings make it harder to identify what is actually driving the trend.