Calorie Surplus (Bulking) Calculator

How big should a surplus be for a lean bulk?

Muscle grows slowly, so the surplus should be small: about 250–500 calories a day above TDEE (10–20%) for most people, toward the lower end for experienced lifters and the higher end for beginners or underweight adults. Bigger surpluses add fat faster than muscle.

Calories to gain weight per week

A 250–500-calorie daily surplus corresponds to roughly 0.25–0.5 kg (0.5–1 lb) of body weight per week on paper; real gains are often slower because some surplus is burned off. Beginners can expect around 0.5–1 kg of muscle per month; after a few years of training, a few kilograms per year is normal.

Macros in a surplus

Protein 1.4–2.0 g/kg (ISSN), fat 20–35% of calories, carbohydrate makes up the rest and fuels training. Push the extra calories mostly into carbs around workouts. The macro calculator turns the total into grams.

Bulking for beginners

Three or more resistance sessions a week with progressive overload, 7–9 hours of sleep and a modest surplus beat any “dirty bulk”. Weigh yourself 3–4 times a week and average it; if the weekly average climbs faster than 0.5 kg, trim 100–200 calories.

Sources

• ISSN Position Stand: protein and exercise, 2017 — https://pubmed.ncbi.nlm.nih.gov/28642676/
• Dietary Guidelines for Americans (current edition) — https://www.dietaryguidelines.gov/
• Mifflin-St Jeor equation — https://pubmed.ncbi.nlm.nih.gov/2305711/

This calculator is educational and not medical advice. If you have a health condition, are pregnant, or are under 18, ask a clinician before changing your diet.