So you want to bulk up and gain some muscle? Then look no further! This calculator will help you figure out the right calories and macros for doing so.

You might not know how much you weigh in kilograms offhand; here's a conversion tool at the bottom to help with that.


And here are the different "Activity Level" options for you to consider:

  • Sedentary (1 hour or less of exercise weekly) = 1.2
  • Lightly Active (2-3 hours of weekly exercise) = 1.4
  • Moderately Active (4-5 hours of weekly exercise) = 1.55
  • Very Active (1 hour of daily exercise) = 1.7
  • Extremely Active (2 hours of daily exercise) = 2.0

Simply input the appropriate numbers in the fields above and it will show what your recommended calories and macros for bulking are!

Diving into the Formula

For those of you who are curious about how this calculator works, it's quite simple. This page uses arguably the most accurate equation for calorie calculations: the Katch-McArdle formula. This formula, which is widely used across the fitness space, calculates your BMR (basal metabolic rate) through the following:

BMR = 370 + (21.6 * LBM)

The number from this formula is how many calories you need to consume to maintain your current weight. Unfortunately, this assumes that your body is in a state of TOTAL REST. Multipliers need to be applied depending on your current level of activity. As such, pull a number from the list above that most closely matches the physical activity your current lifestyle.

Once you have that factor applied, you'll have the number of calories needed to maintain your bodyweight.

But we don't want to maintain weight; we want to BULK UP! As such, the total calories above are roughly 110% of this number. By consuming 10% more calories than what your body requires for maintenance, you will enter a steady state of weight gain (roughly 0.5 - 1.0 pounds a week).

Of course, you don't want to just gain weight; you want to BUILD MUSCLE without piling on tons of unnecessary fat. For that reason, we need a proper macronutrient ratio for your fat loss. Macros can vary slightly from person to person, but generally, I've found these percentages of caloric intake (total calories that you consume) to be the best macros for burning off unwanted fat:

  • Carbs - 50%
  • Protein - 20%
  • Fat - 30%

So that's how the calculator works; make sure you try it out!