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Free Tool

Cutting Calorie Calculator

Uses the Katch-McArdle BMR formula. Enter your stats and get your exact daily targets — calories, protein, carbs, and fat — plus a week-by-week projection.

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How This Calculator Works

This calculator uses the Katch-McArdle BMR formula, which is more accurate than Mifflin-St Jeor or Harris-Benedict for athletes because it accounts for lean body mass rather than total weight.

The Formula

Step 1: Calculate Lean Body Mass (LBM)
LBM = Body Weight × (1 − Body Fat% ÷ 100)

Step 2: Calculate BMR
BMR = 370 + (21.6 × LBM in kg)

Step 3: Calculate TDEE
TDEE = BMR × Activity Multiplier

Step 4: Calculate cutting calorie target
Cutting Calories = TDEE − (fat to lose × 7,700 ÷ days available)

Step 5: Set macros
Protein = 2.2g × LBM(kg) | Fat = 0.8g × body weight(kg) | Carbs = Remaining calories ÷ 4

Accuracy Note

No calculator is perfectly accurate — your actual TDEE can vary by ±10–15% based on non-exercise activity thermogenesis (NEAT), metabolic adaptation, and hormonal factors. Use these numbers as your starting point, then adjust every 2 weeks based on actual results.

If you're losing faster than projected: add 100–200 calories, primarily from carbs.
If you're not losing: subtract 100–200 calories from carbs.