Resting Metabolic Rate (Schofield) Calculator

How it is calculated

The tool picks a pair of constants by sex and age band, then applies a straight line: RMR = a × weight + b, with weight in kilograms and RMR in kcal per day. The bands are under 3, 3–9, 10–17, 18–29, 30–59 and 60 or older (age can be fractional), each with its own a and b for men and women. For a woman aged 30–59 it is 8.126 × weight + 845.6; for a man of that age 11.472 × weight + 873.1. Two daily totals are added by multiplying RMR by 1.2 (sedentary) and 1.55 (active). Height is not used, and anything other than female is treated as male. Weight outside 2–650 kg, an age of 0 or below or above 130, or an empty box shows no result. The constants jump at band edges, so the result can change abruptly at 30 or 60.

Common mistakes

• Entering weight in pounds. The coefficients assume kilograms and the result would be more than double.
• Reading the sedentary and active lines as calorie targets for losing weight. They are estimated maintenance levels, so a deficit has to be subtracted.
• Expecting height or muscle mass to change the answer. This equation ignores both, so a tall lean athlete and a short heavy person with the same weight and age get the same RMR.
• Comparing results across band edges without expecting a step. For a 70 kg woman, age 29 gives 1,524 kcal/day but age 30 gives 1,414 kcal/day.
• Entering an age in months for an infant. The field is in years, so a 6-month-old is 0.5.