Body Recomposition Calculator
Plan your body recomposition: lose fat while preserving muscle. Get calorie targets, protein goals, and weekly milestones.
Quick Answer
Body recomposition means losing fat and building (or preserving) muscle simultaneously. It requires a moderate calorie deficit on rest days, a slight surplus on training days, high protein intake (1g/lb body weight), and progressive resistance training. Expect to lose 0.5-1 lb of fat per week while maintaining lean mass over 12-20 weeks.
Average men: 18-24%. Average women: 25-31%. Use calipers, DEXA, or visual estimate.
Athletic men: 10-14%. Athletic women: 18-22%. Visible abs: men ~12%, women ~20%.
Your Recomposition Plan
Daily Calorie Targets (Calorie Cycling)
Weekly Milestones
| Week | Weight | Body Fat % | Fat Mass |
|---|---|---|---|
| Start | 180 lbs | 25% | 45 lbs |
| Week 2 | 177.4 lbs | 23.9% | 42.4 lbs |
| Week 4 | 174.7 lbs | 22.7% | 39.7 lbs |
| Week 6 | 172.1 lbs | 21.5% | 37.1 lbs |
| Week 8 | 169.4 lbs | 20.3% | 34.4 lbs |
| Week 10 | 166.8 lbs | 19% | 31.8 lbs |
| Week 12 | 164.1 lbs | 17.7% | 29.1 lbs |
| Week 14 | 161.5 lbs | 16.4% | 26.5 lbs |
| Week 16 | 158.8 lbs | 15% | 23.8 lbs |
About This Tool
The Body Recomposition Calculator helps you plan a simultaneous fat loss and muscle preservation (or gain) program by computing your current body composition, projecting your goal physique, and providing calorie cycling targets with weekly milestones. Unlike simple weight loss calculators that treat all weight the same, this tool distinguishes between lean mass and fat mass, which is critical for anyone who wants to look better, not just weigh less. Body recomposition is the gold standard approach for anyone who is new to resistance training, returning after a break, or carrying significant body fat alongside reasonable muscle mass.
What Is Body Recomposition?
Body recomposition (often called “recomp”) is the process of simultaneously losing body fat and building or maintaining lean muscle mass. Traditional approaches separate fat loss (cutting) and muscle building (bulking) into distinct phases, but research increasingly shows that simultaneous recomposition is achievable, especially for beginners, those returning to training, and individuals with higher body fat percentages. The key insight is that your body can pull energy from stored fat to fuel muscle protein synthesis, provided the calorie deficit is moderate and protein intake is sufficient.
How the Calculator Works
This calculator uses your current weight and body fat percentage to determine your lean mass and fat mass. It assumes lean mass is preserved throughout the recomposition period, which is realistic when combined with resistance training and high protein intake. Your goal body fat percentage determines the target weight (since lean mass stays constant, losing fat reduces total weight). The Katch-McArdle formula estimates your basal metabolic rate based on lean body mass, which is more accurate for this context than formulas based on total weight. Activity multipliers scale BMR to your Total Daily Energy Expenditure (TDEE).
The Calorie Cycling Approach
The calculator prescribes different calorie targets for training days and rest days. On training days (typically 4 per week), you eat slightly above maintenance to support muscle protein synthesis and fuel intense workouts. On rest days (3 per week), you eat below maintenance to create the weekly calorie deficit needed for fat loss. This cycling approach is supported by research showing that nutrient timing around resistance training sessions enhances the partitioning effect, directing calories toward muscle growth rather than fat storage. The net weekly energy balance still results in fat loss, but the surplus on training days optimizes the anabolic response to exercise.
Why Protein Is Non-Negotiable
The recommended protein intake of approximately 1 gram per pound of goal body weight is based on meta-analyses showing that 1.6-2.2 g/kg of body weight per day maximizes muscle protein synthesis during energy restriction. Protein serves multiple roles during recomposition: it provides the amino acid building blocks for muscle repair and growth, it has the highest thermic effect of food (20-30% of calories from protein are burned during digestion), and it is the most satiating macronutrient, helping control hunger during deficit days. Spreading protein intake across 3-5 meals with 25-40 grams per meal optimizes the muscle protein synthesis response.
Realistic Expectations and Timeline
Body recomposition is slower than aggressive cutting or bulking because you are optimizing for composition rather than weight change alone. Beginners can expect to lose 0.5-1 pound of fat per week while gaining measurable muscle. Experienced lifters may see slower progress. The scale may not move much because fat loss and muscle gain partially offset each other on the scale; track progress with body measurements, progress photos, and strength gains rather than relying solely on body weight. A realistic timeline for noticeable visible change is 8-16 weeks; significant transformation typically takes 16-24 weeks of consistent adherence.