Plateknow BMR is what your body spends at rest; multiply it by how much you move and you have TDEE — maintenance, the calories that hold your weight where it is.
That is the target. The hard part is the other half — knowing what you actually ate.
Download freeBMR formula: Mifflin-St Jeor
Mifflin-St Jeor (1990) is the equation clinical practice usually reaches for: the American Dietetic Association’s evidence analysis found it predicted measured resting energy within 10% more often than the other standard equations — and it still missed by more for a meaningful minority.
- Men — 10 × weight in kg + 6.25 × height in cm − 5 × age + 5
- Women — 10 × weight in kg + 6.25 × height in cm − 5 × age − 161
TDEE calculator: the activity multiplier
| Multiplier | What it describes |
|---|---|
| 1.2 | Desk job, little or no exercise |
| 1.375 | Exercise 1 to 3 days a week |
| 1.55 | 3 to 5 days a week |
| 1.725 | 6 to 7 days a week |
| 1.9 | Physical job, or two sessions a day |
These multipliers are conventional and the weakest link: 1.2 to 1.9 is a 58% swing on the same body. Read the result as a starting bracket, not a figure.
What is a calorie deficit?
Eating below maintenance — the TDEE above, minus something. This calculator does not choose that something: a deficit is a target, and the decision is yours to make, with a clinician’s advice.
Daily fiber intake, and the Daily Values on the label
The result includes fibre (fiber), which the 2025–2030 Dietary Guidelines lead on alongside protein. The Adequate Intake is 14 g per 1,000 calories (Dietary Reference Intakes); the FDA Daily Value of 28 g is that rule at 2,000 calories.
| Nutrient | Daily Value |
|---|---|
| Dietary fibre | 28 g |
| Protein | 50 g |
| Total fat | 78 g |
| Saturated fat | 20 g |
| Total carbohydrate | 275 g |
| Added sugars | 50 g |
| Sodium | 2,300 mg |
A Daily Value lets you compare one food with another; it is not a target for you.
What is the difference between BMR and TDEE?
BMR is the energy you spend at complete rest. TDEE is BMR multiplied by an activity factor — the calories that keep your weight steady.
Why is my TDEE different on another calculator?
Almost always the activity multiplier, the one input with no agreed definition. Some calculators also use Harris-Benedict or Katch-McArdle instead of Mifflin-St Jeor.
How accurate is a BMR calculator?
For most adults a predictive equation lands within about 10% of measured resting energy, and for a meaningful minority it does not. Recording what you actually eat over a few weeks is the only way to find out which you are.
Is TDEE how much I should eat?
No. It is how much holds your weight steady. What you should eat is a bigger decision than an equation, and this page does not make it for you.
Mifflin MD, St Jeor ST et al., A new predictive equation for resting energy expenditure in healthy individuals, Am J Clin Nutr (1990). Frankenfield D et al., American Dietetic Association evidence analysis of predictive equations for resting metabolic rate, J Am Diet Assoc (2005). Institute of Medicine, Dietary Reference Intakes (2005) — fibre Adequate Intake 14 g per 1,000 kcal. FDA, Daily Values on the Nutrition and Supplement Facts labels. Dietary Guidelines for Americans 2025–2030, released 7 January 2026.