Cutting Calculator
Calculate your optimal cutting calories, protein floor, and fat loss timeline to cut body fat while preserving muscle
Your Cutting Plan
Understanding the Cutting Phase
A cutting phase is a structured period of caloric restriction designed to reduce body fat while preserving as much lean muscle mass as possible. Unlike casual dieting, cutting is a deliberate strategy used by athletes, bodybuilders, and fitness enthusiasts who want to reveal muscle definition and reach a specific body fat percentage. The key distinction is that cutting prioritizes fat loss over scale weight -- the goal is to lose adipose tissue, not simply weigh less. A well-executed cut maintains strength, energy, and metabolic health throughout the process.
The foundation of any cut is a moderate calorie deficit, typically 300 to 500 calories below your Total Daily Energy Expenditure (TDEE). Research from 2024-2025 consistently shows that deficits in this range produce steady fat loss of approximately 0.5 to 1.0 percent of bodyweight per week while minimizing muscle catabolism. Larger deficits of 500 to 750 calories per day can accelerate fat loss but carry greater risk of muscle wasting, hormonal disruption, and metabolic adaptation -- a phenomenon where your body reduces its energy expenditure in response to sustained under-eating. Deficits above 1000 calories per day are generally not recommended except under medical supervision.
Protein intake is the single most important nutritional variable during a cut. Current evidence recommends consuming between 2.0 and 2.4 grams of protein per kilogram of bodyweight per day during a caloric deficit, with intakes as high as 2.7 g/kg justified for large deficits or very lean individuals. This elevated protein floor serves multiple functions: it stimulates muscle protein synthesis to counteract breakdown, increases satiety to make the deficit easier to sustain, and has a high thermic effect that effectively burns 20-30 percent of its own calories during digestion. Dropping protein below 1.8 g/kg during a cut significantly increases the risk of losing hard-earned muscle tissue.
The rate at which you lose body fat matters as much as the total amount you lose. Safe fat loss rates fall between 0.5 and 1.0 percent of total bodyweight per week. Losing faster than 1.0 to 1.5 percent per week dramatically increases muscle loss risk, even with high protein intake and resistance training. Leaner individuals (below 15 percent body fat for men or 22 percent for women) should aim for the slower end of this range, as the body becomes increasingly resistant to further fat loss and more likely to sacrifice muscle when stores are already low. Plan your cutting timeline realistically and include periodic diet breaks or refeed days every 6-8 weeks to reset metabolic hormones and prevent adaptive thermogenesis.
How to Use This Cutting Calculator
- Select your gender and choose your preferred unit system (kg or lbs) using the toggles. Enter your current body weight and height accurately -- these are used to calculate your TDEE via the Mifflin-St Jeor equation.
- Enter your age in years. Your metabolic rate decreases with age, so this helps the calculator estimate your baseline calorie expenditure more accurately.
- Input your current body fat percentage. If you do not know your body fat, use a body fat calculator or estimate based on visual references. Then enter your target body fat percentage -- a realistic target typically falls between 8-15% for men and 16-25% for women.
- Set your desired timeline in weeks. A typical cut ranges from 8 to 20 weeks. The calculator will tell you whether your timeline is realistic based on safe fat loss rates and will warn you if the required deficit is too aggressive.
- Click "Calculate Cutting Plan" to see your personalized results. Review your cutting calories, protein floor, weekly loss rate, and the deficit severity gauge. Pay attention to any warning banners -- green means safe, yellow means aggressive, and red means the plan needs adjustment.
Frequently Asked Questions
How many calories should I eat while cutting?
Your cutting calories depend on your Total Daily Energy Expenditure (TDEE) minus a deficit of 300-500 calories per day. For most men, this typically ranges from 1800-2500 kcal per day, and for women from 1400-2000 kcal per day. Never drop below 1500 kcal per day for men or 1200 kcal per day for women without medical supervision, as this risks nutrient deficiencies and significant metabolic adaptation. The exact number varies based on your size, activity level, and how aggressively you want to cut.
How much protein do I need during a cut?
During a caloric deficit, protein requirements increase compared to maintenance. Research recommends 2.0-2.4 grams of protein per kilogram of bodyweight daily (approximately 0.9-1.1 g/lb). With larger deficits, intakes up to 2.7 g/kg may be beneficial. For an 80 kg person, this means 160-216 grams of protein per day. High protein intake during cutting preserves muscle mass, increases satiety, and has a high thermic effect -- your body burns about 25% of protein calories just processing them.
What is a safe rate of fat loss per week?
A safe rate of fat loss is 0.5-1.0% of your total bodyweight per week. For a 180 lb (82 kg) person, that equals roughly 0.9-1.8 lbs (0.4-0.8 kg) per week. Rates above 1.0-1.5% of bodyweight per week significantly increase the risk of muscle loss, even with optimal protein intake and training. Leaner individuals should target the lower end of this range because the body becomes more resistant to fat loss and more prone to muscle catabolism at lower body fat levels.
How long should a cutting phase last?
Most cutting phases last between 8 and 20 weeks, depending on how much fat you need to lose. A general guideline is to lose no more than 1% of bodyweight per week and to take a diet break (eating at maintenance for 1-2 weeks) every 6-8 weeks of continuous dieting. Extended cuts beyond 20 weeks should incorporate multiple diet breaks. If you need to lose a significant amount of body fat, consider multiple shorter cutting phases separated by maintenance periods rather than one long, grueling cut.
Will I lose muscle during a cut?
Some muscle loss during a cut is nearly unavoidable, but you can minimize it significantly with the right approach. The three key strategies are: maintaining high protein intake (2.0-2.4 g/kg/day), continuing progressive resistance training (do not reduce training volume dramatically), and keeping the caloric deficit moderate (300-500 kcal/day). Research shows that with these practices in place, you can retain 85-95% of your muscle mass during a well-structured cut. Crash diets and excessive cardio without adequate protein are the biggest contributors to muscle loss.
What should my macros be while cutting?
During a cut, prioritize protein first at 2.0-2.4 g/kg bodyweight. Set dietary fat at 0.8-1.0 g/kg (minimum 20% of total calories) to support hormone production. Fill the remaining calories with carbohydrates. For example, on a 2000 kcal cut for an 80 kg person: protein = 176g (704 kcal), fat = 67g (603 kcal), carbs = 173g (693 kcal). Keep fat above 0.7 g/kg minimum to avoid hormonal disruption, especially testosterone and estrogen production.
What is the difference between cutting and simply losing weight?
Cutting specifically aims to lose body fat while preserving lean muscle mass, whereas general weight loss does not differentiate between fat and muscle. A cutting approach involves higher protein intake, continued resistance training, and moderate caloric deficits. General weight loss often involves larger deficits, less attention to protein, and may sacrifice considerable muscle tissue. The result is that a successful cut improves your body composition and reveals muscle definition, while casual weight loss may leave you lighter but with a similar or worse body fat percentage.
