Calculator inputs
Example data table
| Profile | Calories | Protein | Carbs | Fat | Weekly Loss |
|---|---|---|---|---|---|
| Male, 80 kg, 18% body fat | 2,137 kcal | 151 g | 228 g | 56 g | 0.49 kg |
| Female, 65 kg, 26% body fat | 1,590 kcal | 111 g | 151 g | 42 g | 0.34 kg |
| Male, 190 lb, 15% body fat | 2,325 kcal | 169 g | 250 g | 61 g | 0.53 kg |
Formula used
1. BMR
Mifflin-St Jeor: BMR = 10W + 6.25H - 5A + S
Here, W is kilograms, H is centimeters, A is age, and S is +5 for males or -161 for females.
2. Lean-mass option
Katch-McArdle: BMR = 370 + 21.6 × lean mass in kg. This needs body fat percentage.
3. Daily energy need
TDEE = BMR × activity factor
4. Cutting calories
Cut calories = TDEE - deficit. The deficit can be a percentage or a fixed calorie value.
5. Protein and fat
Protein grams = chosen body base × protein ratio
Fat grams = body weight in kg × fat ratio
6. Carbohydrates
Carb grams = (cut calories - protein calories - fat calories) ÷ 4
7. Weekly loss estimate
Weekly loss (kg) = daily deficit × 7 ÷ 7700
How to use this calculator
- Enter sex, age, body weight, and height.
- Select your weight and height units.
- Add body fat percentage for lean-mass based planning.
- Choose an activity level close to your true routine.
- Select auto, Mifflin-St Jeor, or Katch-McArdle.
- Set a percentage or fixed calorie deficit.
- Pick whether protein should follow body weight or lean mass.
- Adjust protein, fat, and minimum carb targets.
- Press the calculate button to show results above the form.
- Use the CSV or PDF buttons to save your output.
FAQs
1. What is a cutting macro calculator?
It estimates calorie and macronutrient targets for fat-loss phases. The tool combines body size, activity, deficit size, and macro settings into daily nutrition goals.
2. Why include body fat percentage?
Body fat helps estimate lean mass. That makes protein planning more specific and allows the Katch-McArdle formula to estimate basal needs from lean tissue.
3. Which formula is better for cutting?
Mifflin-St Jeor works well for most people. Katch-McArdle can be helpful when body fat is known and lean-mass driven planning is important.
4. What is a reasonable calorie deficit?
Many people use roughly 10% to 25% below maintenance. Larger deficits can speed loss, but they often reduce training quality, recovery, and diet adherence.
5. Why are protein targets higher while cutting?
Higher protein can support muscle retention, appetite control, and recovery during a calorie deficit. That is why cutting plans often prioritize protein first.
6. Why did the calculator reduce fat grams?
If your calorie target is tight and you set a minimum carbohydrate floor, the calculator may lower fat to keep carbs available without breaking the calorie goal.
7. Is the weekly loss estimate exact?
No. It is an approximation from calorie math. Water shifts, stress, sodium, sleep, and training changes can all affect real scale movement.
8. Can I use this for meal planning?
Yes. The result gives daily calorie, protein, carb, and fat targets. You can split those totals across meals, snacks, or training-day menus.