Body Recomposition Timeline
See how your weight and body fat will change over time based on your calorie deficit.
How this calculator works
Enter your current weight, body fat percentage (use our body fat calculator if unsure), target body fat, and daily calorie deficit. The calculator uses the 7,700 kcal/kg fat equivalence to project weekly fat loss, then models your body composition week by week over your chosen period.
Limitations
This is a linear model. Metabolic adaptation, water weight fluctuations, and changes in training volume all affect real-world outcomes. Treat the projection as a target trajectory, not a guarantee. Check in every 4 weeks and adjust your deficit if progress stalls.
Frequently Asked Questions
- What is body recomposition?
- Body recomposition means simultaneously losing fat and gaining (or maintaining) muscle. In practice it is most achievable in beginners, those returning from a break, or those with higher body fat. Advanced lifters typically need dedicated bulk and cut phases.
- How fast can I lose body fat?
- A 500 kcal/day deficit produces approximately 0.5 kg of fat loss per week (since 1 kg fat ≈ 7,700 kcal). Deficits beyond 750 kcal/day increase the risk of muscle loss. Slower is usually better for preserving strength and muscle tissue.
- Why does projected weight decrease but lean mass stays the same?
- This calculator assumes lean mass is preserved during a cut with adequate protein intake. In practice, some lean mass loss is possible — particularly below 10–12% body fat for men and 18–20% for women. High protein intake and resistance training minimise this.
- How accurate is the projection?
- Projections assume a consistent calorie deficit and no changes in metabolic adaptation. In reality, metabolic rate adapts downward during extended cuts (adaptive thermogenesis), so real progress may slow compared to the linear projection after 8–12 weeks.