BMR — Harris–Benedict Equation

Estimate basal metabolic rate (kcal/day) and your total daily energy expenditure (TDEE). Fields with 🔹 update live.
Required for Harris–Benedict constants.
Enter full years. 🔹
Provide either centimeters or feet+inches. 🔹
Enter body weight in your preferred unit. 🔹
TDEE appears once BMR is available and an activity is selected.
Harris–Benedict estimate in kcal/day.
TDEE = BMR × activity factor.
Fill all inputs to see your personalized summary.
Step-by-step derivation
Provide inputs to see the working with your numbers.
Activity (PAL) reference table
Common factors used to turn BMR into daily calorie needs (TDEE):
1.20 Sedentary (little/no exercise)
1.375 Light (1–3×/wk)
1.55 Moderate (3–5×/wk)
1.725 Very active (6–7×/wk)
1.90 Extra active (physical job)
2.30 Professional athlete
Sources
• Harris JA, Benedict FG. A Biometric Study of Human Basal Metabolism. 1918/1919.
• Roza AM, Shizgal HM. The Harris–Benedict equation reevaluated. Am J Clin Nutr. 1984 (background).
• PAL factors commonly used in dietetics for TDEE estimation.

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