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Resting Metabolic Rate Calculator

RMR from Mifflin-St Jeor, Harris-Benedict and Katch-McArdle side by side.

Enter your values

ⓘ Live results

Results
Resting metabolic rate
1,740 kcal/day
Mifflin-St Jeor
1,728 kcal
Harris-Benedict
1,795 kcal
Katch-McArdle
1,752 kcal
Sedentary total
2,087 kcal/day
Lightly active
2,392 kcal/day
Moderately active
2,696 kcal/day
Very active
3,001 kcal/day

Working

  1. 110 x 78 + 6.25 x 178 - 5 x 34 + 5 = 1,728 kcal

Quick answer

Resting metabolic rate is the energy your body uses at complete rest. Mifflin-St Jeor is the most accurate general equation; Katch-McArdle is better when body fat is known.

Mifflin: 10 x kg + 6.25 x cm - 5 x age + s

How to use the Resting Metabolic Rate Calculator

  1. 1Enter your current weight, height and age.
  2. 2Add body fat percentage if you know it to unlock the Katch-McArdle estimate.
  3. 3Pick the activity multiplier that matches a typical week, not your best week.

Worked example

Using the values the calculator loads with:

Inputs

  • SexMale
  • Weight78 kg
  • Height178 cm
  • Age34 years
  • Body fat (optional)18 %

Results

  • Resting metabolic rate1,740 kcal/day
  • Mifflin-St Jeor1,728 kcal
  • Harris-Benedict1,795 kcal
  • Katch-McArdle1,752 kcal
  • Sedentary total2,087 kcal/day
  • Lightly active2,392 kcal/day
  • Moderately active2,696 kcal/day
  • Very active3,001 kcal/day
  1. 10 x 78 + 6.25 x 178 - 5 x 34 + 5 = 1,728 kcal

Frequently asked questions

What is the difference between RMR and BMR?

BMR is measured after an overnight fast in a lab; RMR is a slightly higher real-world figure. The equations here are used interchangeably for both in practice.

Which equation should I trust?

Mifflin-St Jeor for most people, Katch-McArdle if you have a reliable body fat measurement and carry more muscle than average.

About this calculator

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.