How to Calculate Caloric Surplus
What is Caloric Surplus?
A caloric surplus calculator determines how many calories above your maintenance level (TDEE) to eat for muscle growth. A surplus is required to provide energy for building new muscle tissue.
Formula
daily_surplus = tdee + (weekly_goal_lbs × 3500 / 7); weekly_gain_lbs = weekly_surplus / 3500
- tdee
- TDEE (cal/day) — Total daily energy expenditure
- surplus
- Daily surplus (cal/day) — Extra calories for muscle gain
- gain_lbs
- Weekly weight gain (lbs) — Planned gain rate (0.5–1 lb/week is ideal)
Step-by-Step Guide
- 1Surplus = Target Calories − TDEE (Total Daily Energy Expenditure)
- 2Slow gain: +200 kcal/day → ~0.5kg/month lean mass
- 3Moderate: +350 kcal/day → ~0.75–1kg/month
- 4Fast: +500 kcal/day → ~1–1.5kg/month (more fat gain too)
- 57,700 kcal = approximately 1 kg of body mass
Worked Examples
Input
TDEE 2,500, slow gain
Result
Eat 2,700 kcal/day → ~0.5kg/month
Input
TDEE 3,000, moderate gain
Result
Eat 3,350 kcal/day
Input
TDEE 2,200, aggressive gain
Result
Eat 2,700 kcal/day → ~1kg/month
Frequently Asked Questions
How many calories above TDEE for muscle gain?
300–500 calories per day gains 0.5–1 lb/week. Slow surplus maximises muscle vs. fat gain.
What is TDEE?
Total Daily Energy Expenditure = BMR + calories from activity. For 70 kg person with moderate activity: typically 2,200–2,600 cal/day.
Can I gain muscle slowly?
Yes. Smaller surplus (200–300 cal/day) gains less fat but still builds muscle with progressive training.
Ready to calculate? Try the free Caloric Surplus Calculator
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