BMR vs RMR: Are They the Same Thing?
Not quite the same. RMR (resting metabolic rate) — also called REE (resting energy expenditure) — is the calories you burn at rest under everyday conditions. BMR is the same idea measured under stricter lab conditions, and runs slightly lower. In practice the terms are used interchangeably, and most calculators (including this one) report the result as your BMR.
What's the difference between BMR and RMR?
Both measure the energy your body uses at complete rest — just under different conditions. Basal metabolic rate (BMR) is the strict version: measured after a 12-hour fast, first thing on waking, lying down and fully rested, in a temperature-controlled room. It is the true floor of your metabolism, and it mostly appears in research. Resting metabolic rate (RMR) is the everyday version: measured after a few hours' rest, at any time of day, without the overnight-fasting protocol. Because those conditions are looser, RMR comes out a little higher than BMR — a difference commonly put at around 10%, though published estimates vary.
Is RMR the same as REE?
Yes — resting metabolic rate (RMR) and resting energy expenditure (REE) are two names for the same thing. You'll see both in the literature; they're interchangeable. BMR has a twin too — it's sometimes written as basal energy expenditure (BEE).
Which does the Mifflin-St Jeor equation give?
Strictly, RMR/REE. The Mifflin-St Jeor equation was built in 1990 to predict "resting energy expenditure," and it was derived from RMR-style measurements. But because RMR and BMR are so close, and the words are used loosely even in clinics, almost every calculator — including the one on this site — reports the Mifflin-St Jeor result as your "BMR." So when you see "BMR" on a calculator, it is really your estimated resting metabolic rate.
Does the difference matter for your calorie target?
For everyday calorie planning, no. The gap between BMR and RMR is small, the terms are used interchangeably, and the next step — multiplying your resting figure by an activity factor to get your total daily burn — is itself a rough estimate that swamps that small distinction. Treat the calculator's result as your resting metabolism, use it as the base for your total daily energy needs, or get just the resting figure from the BMR calculator, and adjust from real-world results. The precise BMR-vs-RMR wording matters for accuracy and understanding, not for your day-to-day numbers.
Common questions
Is BMR the same as RMR?
Almost, but not exactly. They measure the same thing — the calories you burn at rest — but under different conditions. BMR is measured under strict basal conditions; RMR is measured under everyday resting conditions and comes out a little higher, a difference commonly put at around 10% (though published estimates vary). In normal use the two terms are used interchangeably.
What does RMR stand for?
Resting metabolic rate — the energy your body uses at rest. It is also called resting energy expenditure (REE); the two terms mean the same thing.
Is RMR the same as REE?
Yes. RMR (resting metabolic rate) and REE (resting energy expenditure) are two names for the same measurement.
Does the Mifflin-St Jeor equation give BMR or RMR?
Technically RMR/REE — its 1990 paper predicts "resting energy expenditure." Because RMR and BMR are so close and are used interchangeably, this and almost every calculator report the result as your BMR.
Is RMR higher or lower than BMR?
Higher, though only modestly — the gap is commonly put at around 10%, but published estimates vary. RMR is measured under looser conditions (you need not be fasted overnight or measured on waking), so it captures a little more than the strict basal minimum.