Bulking Calculator - Muscle Gain Calories
Calculate your optimal calorie surplus and macros for lean muscle gain, or track your body composition with AI-powered photo analysis.
The Science of Bulking
Research shows that optimal muscle gain requires a precise calorie surplus. According to a 2020 systematic review published in Sports Medicine, natural lifters can gain approximately 0.25-0.5kg (0.5-1lb) of muscle per month—meaning large surpluses beyond 200-500 calories mostly result in fat gain, not additional muscle.
Optimal Surplus
Research suggests a moderate surplus maximizes muscle gain while minimizing fat accumulation
Muscle Gain Rate
Natural lifters can expect to gain 0.5-1lb of muscle per month under optimal conditions
Protein Requirements
Meta-analyses show 1.6-2.2g protein per kg bodyweight optimizes muscle protein synthesis
Bulking Calorie Calculator
Calculate Bulking Calories
Your data is not stored. This is a client-side calculation only.
Track Your Muscle Gains
See what you're actually gaining
Are you building muscle or just fat? PhysiqueAI's free body scan tracks your lean mass and body fat so you know if your bulk is working.
- Track lean mass vs fat gain over time
- Weekly body composition scans
- See if your surplus is too high or too low
- 15+ body composition metrics
- Works with mirror selfies
No credit card required
What the Research Says
Optimal Calorie Surplus for Muscle
A 2019 review in the Journal of the International Society of Sports Nutrition found that for building muscle while minimizing fat gain:
- A surplus of 200-500 calories maximizes muscle protein synthesis
- Larger surpluses (>500 cal) increase fat gain without additional muscle
- Beginners may benefit from slightly higher surpluses due to "newbie gains"
Realistic Muscle Gain Rates
Research from the American College of Sports Medicine shows natural muscle gain potential varies by training experience:
- Beginners: ~2 lbs muscle/month (first year)
- Intermediate: ~1 lb muscle/month (years 2-3)
- Advanced: 0.5 lbs or less/month (4+ years)
Bulking Tips for Maximum Gains
Do This
- Train hard with progressive overload
- Hit protein target daily (0.8-1g/lb)
- Sleep 7-9 hours for recovery
- Track weight weekly, adjust as needed
- Stay lean bulk if over 15% body fat
Avoid This
- Dirty bulking (excessive surplus)
- Skipping workouts while eating surplus
- Neglecting vegetables and fiber
- Bulking above 20% body fat
- Changing calories every few days
Track your bulk progress
See if your bulk is building muscle or just fat. PhysiqueAI's free body scan tracks your muscle mass and body fat percentage over time.
No credit card required • 3 free scans/month