Macro calculator

Maintenance comes from the Mifflin-St Jeor equation and an activity multiplier, as in the TDEE calculator, or from the maintenance calories you enter. The goal sets a weekly rate as a share of body weight, and the rate becomes a daily difference at 7,700 kcal per kg. The calories left after protein are split between fat and carbs.

rate (kg/week) = weight (kg)
  × pace (%) / 100
  (negative for a cut, 0 to maintain)
calories = round(maintenance
  + rate × 7,700 / 7)
protein (g) = round(weight (kg)
  × protein (g/kg))
fat (g) = round(max(
  0.6 × weight (kg),
  (calories − 4 × protein)
    × fat share / 9))
carbs (g) = round(
  (calories − 4 × protein
    − 9 × fat) / 4)

The fat share is 0.40 for Balanced, 0.25 for More carbs and 0.60 for More fat. Fat never drops below 0.6 g per kg, and carbs take the rest. Protein and carbs count 4 kcal per gram and fat 9, so after rounding the grams can differ from the calories by a few kcal. Shares in the result are of the energy the three macros provide.

The weekly pace runs from 0.25 to 1% of body weight for a cut and from 0.1 to 0.5% for a bulk. Pendum Macros recommends 0.5 to 1% for a cut and 0.1 to 0.25% for a bulk; its slider reaches 1.5% for a mini-cut of 2 to 4 weeks.

The protein levels are the four Pendum Macros offers: 1.4, 1.6, 2.0 and 2.2 g/kg, with 1.6 g/kg the default. The ISSN position stand finds 1.4 to 2.0 g/kg a day sufficient for most people who exercise, and says 2.3 to 3.1 g/kg may be needed to maximize lean-mass retention in resistance-trained people during a calorie deficit. The levels here stop at 2.2 g/kg, below that range.

Targets are generated only between 1,500 and 5,000 kcal a day, from a maintenance of 1,200 to 5,000 kcal, and only while carbs stay at zero or above. These are the limits Pendum Macros uses: product limits, not individual safety thresholds.

Pendum Macros also refuses a cut when BMI is under 18.5 or the goal weight is under BMI 18.5, and it caps the weekly rate at the distance to the goal weight. This calculator has no goal weight, so the weight after one week at the chosen pace stands in for the goal: a cut is not generated when BMI is under 18.5 now, or would be after that week. When the cut is generated, its targets are the ones the app gives for that goal.

For example, at 180 cm and 80 kg, cutting at 0.5% a week from a maintenance of 2,600 kcal loses 0.4 kg a week, or 440 kcal a day, so calories are 2,160. Protein at 1.6 g/kg is 128 g. Balanced fat is (2,160 − 512) × 0.40 / 9 = 73 g, which leaves 248 g of carbs.

7,700 kcal per kg (3,500 per lb) is a short-term approximation. The energy in a kilogram lost depends on body fat, and expenditure falls as weight changes, so over months the real rate drifts from the plan.