Body Recomposition Calculator
Plan your body recomposition with calorie targets, protein recommendations, and a realistic timeline.
Medical disclaimer: This calculator is provided for educational and informational purposes only and does not constitute medical advice, diagnosis, or treatment. Results are general estimates and may not reflect your individual circumstances. Always consult a qualified healthcare professional before making decisions about your health.
Body Recomposition Calculator
Calculator
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Formula: Goal Weight = Lean Mass / (1 - Goal BF%)
Worked example — Goal weight: 159 lbs | Daily target: 2,038 cal | Protein: 135g
Formula
Goal Weight = Lean Mass / (1 - Goal BF%)
First, calculate current lean mass: Weight × (1 - Body Fat%). Then find goal weight by dividing lean mass by (1 - goal BF%). The difference is fat to lose. Daily deficit = (fat to lose × 3,500) / (weeks × 7). Protein is set at 1g per pound of lean mass for muscle preservation.
Worked Examples
Example 1: Standard Male Recomp
Problem:180-lb male at 25% body fat wants to reach 15% body fat in 16 weeks.
Solution:Current lean mass: 180 × 0.75 = 135 lbs Current fat mass: 180 × 0.25 = 45 lbs Goal weight (maintaining lean mass): 135 / 0.85 = 158.8 lbs Fat to lose: 180 - 158.8 = 21.2 lbs Weekly loss: 21.2 / 16 = 1.32 lbs/week Daily deficit: 1.32 × 3,500 / 7 = 662 cal/day Maintenance estimate (15 cal/lb): 180 × 15 = 2,700 cal Target calories: 2,700 - 662 = 2,038 cal Protein: 135g | Fat: 58g | Carbs: 243g
Result:Goal weight: 159 lbs | Daily target: 2,038 cal | Protein: 135g
Example 2: Conservative Female Recomp
Problem:145-lb female at 30% body fat wants to reach 22% in 20 weeks.
Solution:Current lean mass: 145 × 0.70 = 101.5 lbs Current fat mass: 145 × 0.30 = 43.5 lbs Goal weight: 101.5 / 0.78 = 130.1 lbs Fat to lose: 145 - 130.1 = 14.9 lbs Weekly loss: 14.9 / 20 = 0.74 lbs/week Daily deficit: 0.74 × 3,500 / 7 = 372 cal/day Maintenance estimate (15 cal/lb): 145 × 15 = 2,175 cal Target calories: 2,175 - 372 = 1,803 cal
Result:Goal weight: 130 lbs | Daily target: 1,803 cal | Protein: 102g
Example 3: Standard male recomp example
Problem:A 180 lb male at 25 percent body fat wants to reach 15 percent body fat in 16 weeks.
Solution:Current lean mass is about 135 lbs and fat mass is about 45 lbs. Keeping lean mass constant, the projected goal weight is about 159 lbs. That means losing about 21 lbs of fat over 16 weeks, or about 1.3 lbs per week.
Result:Goal weight: about 159 lbs | Daily target: about 2,038 cal | Protein: about 135 g
Frequently Asked Questions
What is body recomposition?
Body recomposition means improving body composition by reducing fat mass while trying to preserve or gradually build lean mass. It usually works best with moderate calorie control, adequate protein, and consistent strength training.
How much protein helps during a recomp phase?
Many users do well with roughly 0.8 to 1.0 grams of protein per pound of lean mass during a recomp phase. Protein matters because it supports recovery, satiety, and muscle retention during a calorie deficit.
How fast should body fat come down?
A slower, steadier pace is usually better for preserving performance and lean mass. If the required weekly loss is very aggressive, stretching the timeline often makes the plan more realistic.
Should I bulk or recomp first?
Users with higher body-fat levels often prefer recomp or fat-loss phases before a surplus, while leaner users chasing muscle gain may do better with a small controlled bulk. The better choice depends on body-fat level, training age, and the main goal.
How is goal weight derived from a target body-fat percentage?
Lean mass is found first, as current weight minus current fat mass. Holding that lean mass constant, goal weight is lean mass divided by one minus the target body-fat fraction. For a 180 lb person at 25 percent, lean mass is 135 lb, and a 15 percent target gives 135 divided by 0.85, or about 159 lb. The difference between current and goal weight is therefore the fat that has to come off.
Why does the projection hold lean mass constant?
It is the conservative middle case. Assuming lean-mass gain would flatter the projection, and assuming lean-mass loss would understate what a well-run programme achieves. Holding it flat isolates the fat compartment so the arithmetic stays transparent. In practice a beginner or a returning trainee may add lean tissue and finish heavier than projected at the same body-fat percentage, while a poorly supported deficit finishes lighter and less lean than the plan intended.
Which training variables actually drive a recomposition?
Progressive overload is the core signal: adding load, reps or quality sets over time so the stimulus keeps outrunning current capacity. Weekly working sets per muscle group, proximity to failure, and consistent recovery matter more than exercise selection. Sleep and stress management sit alongside them, because both affect recovery capacity. Without that training stimulus, a calorie deficit produces weight loss rather than a change in composition.
How should I measure body-fat percentage for this estimate?
Every accessible method carries error: bioelectrical impedance scales are sensitive to hydration, skinfold calipers depend heavily on technique, and scan-based methods are more consistent but less available. Because the goal weight is derived from lean mass, an error in the input moves the target directly. The practical answer is to use one method, under the same conditions each time, and pay attention to the direction of change rather than the absolute figure.
What is the difference between a recomposition and a straight cut?
A cut prioritises the fastest tolerable rate of fat loss and accepts that some performance and lean tissue may be sacrificed. A recomposition deliberately slows that rate, keeps intake near maintenance or in a small deficit, and pushes protein and training hard so the composition shifts while weight moves little. A cut is usually the better choice when body fat is high or a deadline is fixed; recomposition suits a longer horizon.
Why do tape measurements and photos beat scale weight during a recomposition?
Because a recomposition is designed to move fat mass and lean mass in opposite directions, the scale is the one metric that can stay still while everything else changes. Waist circumference tracks the abdominal fat depot that is usually shifting, and photographs taken in the same light and pose capture changes the numbers miss. Used together with a weekly weight average, they give a far more honest read on progress.
References
Reviewed for accuracy by Rahul Singh, Health & Wellness Specialist · Editorial policy
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