Free Health Calculators

23 free tools to understand your health data — no sign-up, no tracking, all calculations happen in your browser.

Heart & Cardiovascular

Heart Rate Zone Calculator

Find your 5 training zones from age and resting heart rate.

Max Heart Rate Calculator

Estimate your maximum heart rate using age-based formulas.

Resting Heart Rate Checker

Interpret your resting heart rate and what it means for fitness.

HRV Score Interpreter

Understand your heart rate variability score and recovery status.

Blood Pressure Category Checker

Check which blood pressure category your reading falls into.

Body Composition

Biological Age Estimator

Estimate your biological age from key health and fitness metrics.

Body Fat Percentage Calculator

Calculate body fat percentage using the US Navy or BMI method.

Lean Body Mass Calculator

Find your lean body mass from weight and body fat percentage.

Calculate your basal metabolic rate using Mifflin-St Jeor or Harris-Benedict.

TDEE Calculator

Estimate total daily energy expenditure based on activity level.

Waist-to-Hip Ratio Calculator

Assess cardiovascular risk from your waist and hip measurements.

Sleep

Sleep Cycle Calculator

Find the best bedtimes and wake-up times based on 90-minute sleep cycles.

Sleep Debt Calculator

Calculate accumulated sleep debt and how long to recover it.

Activity & Fitness

VO2 Max Fitness Checker

Interpret your VO2 max score and see how it compares by age and sex.

Steps to Calories

Convert daily step count to calories burned based on your weight and pace.

Steps to Distance

Convert steps to kilometres or miles using stride length.

Running Pace Calculator

Calculate pace, speed, and finish time for any run distance.

One Rep Max (1RM)

Estimate your one-rep maximum from a submaximal lift.

Calorie Deficit Calculator

Find the calorie deficit needed to reach your target weight.

Nutrition & Blood

Hydration Calculator

Estimate your daily water intake target from weight and activity.

Blood Glucose Level Checker

Interpret a blood glucose reading and understand what it means.

SpO2 Level Checker

Check your blood oxygen saturation level and what the range means.

Protein Intake Calculator

Calculate your daily protein target for muscle maintenance or growth.

All metrics, automatically tracked.

Download HC Webhook and sync your health data in real time. Stream heart rate, sleep, steps, blood oxygen, and more to any webhook endpoint — automatically, in the background.

Get it on Google Play

Download on the App Store