Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

VO2 Max Estimator (Resting Heart Rate)

Estimates your VO2 max — the maximum amount of oxygen your body can use during intense exercise — from your resting heart rate and age, with no treadmill test required. It uses the Uth–Sørensen heart-rate-ratio method, a quick proxy for cardiorespiratory fitness.

Resting Heart Rate (bpm)

Age (years)

Fitness

TDEE Calculator

Calculate Total Daily Energy Expenditure (TDEE) by computing BMR via Harris-Benedict equation, then multiplying by an activity factor. Use it as the foundation for evidence-based weight management, sports nutrition, and meal planning.

Body Weight (kg)

Height (cm)

Age (years)

Gender

Activity Level

Key differences

	VO2 Max Estimator (Resting Heart Rate)	TDEE Calculator
Category	Fitness	Fitness
Inputs required	2	5
Result	Estimated VO2 Max (ml/kg/min)	Total Daily Energy Expenditure (calories)
What it does	Estimates your VO2 max — the maximum amount of oxygen your body can use during intense exercise — from your resting heart rate and age, with no treadmill test required. It uses the Uth–Sørensen heart-rate-ratio method, a quick proxy for cardiorespiratory fitness.	Calculate Total Daily Energy Expenditure (TDEE) by computing BMR via Harris-Benedict equation, then multiplying by an activity factor. Use it as the foundation for evidence-based weight management, sports nutrition, and meal planning.