Health & Fitness Calculators
Track your wellness journey with accurate health insights and metrics.
Take control of your well-being with our scientifically-backed Health & Fitness Calculators. From tracking Body Mass Index (BMI) and daily calorie needs to estimating body fat percentage and ideal weight, these tools offer valuable insights to support your fitness journey. Perfect for athletes, health enthusiasts, and anyone looking to lead a healthier lifestyle.
All Calculators89
BMI Calculator — Check Your Body Mass Index (WHO Standard)
Enter height and weight → instantly see your BMI score, WHO weight category, and healthy weight range. Supports metric and imperial measurements, with the WHO adult weight categories shown alongside the number.
TDEE Calculator
Estimate total daily energy expenditure from body size and activity level.
Heart Rate Zones Calculator
Estimate five training zones from age and resting heart rate.
Daily Water Intake Calculator
Estimate a daily fluid target from body weight and exercise.
Macro Split Calculator
Turn daily calories into protein, carbohydrate and fat targets.
Running Pace Calculator
Find pace per kilometre and speed from distance and time.
One-Rep Max Calculator
Estimate your one-rep max and training percentages from a set.
Clothing size
Estimate a letter clothing size from chest, waist and hip measurements.
Lean body mass
Estimate lean mass by subtracting fat mass from body weight, with a Boer formula cross-check.
Shoe size
Convert foot length into common US, UK and EU shoe sizes.
Basal calories
Estimate the calories your body needs at complete rest.
Bedtime
Work backwards from a target wake time to a bedtime that fits complete sleep cycles.
Blood glucose unit
Convert blood glucose between mg/dL and mmol/L.
Blood pressure category
Classify a blood pressure reading using standard screening thresholds.
Calorie deficit
Find the daily calorie deficit needed to reach a weight goal by a chosen date.
Cycling calories
Estimate calories burned cycling from pace, time and body weight.
Healthy weight range
Find the weight range associated with a healthy BMI for your height.
Max heart rate
Estimate maximum heart rate using age-based formulas.
Protein per kg
Turn body weight and a training goal into a protein intake range.
Protein target
Calculate a daily protein target from weight, goal and activity level.
Running calories
Estimate calories burned running from pace, time and body weight.
Sleep cycle
Check how many complete sleep cycles fit between a bedtime and a wake time.
Sleep debt
Estimate accumulated sleep loss over a number of nights.
Steps to distance
Convert a step count into distance using your stride length.
Waist-to-height ratio
Screen central fat distribution with a waist-to-height ratio.
Waist-to-hip ratio
Compare waist and hip measurements to screen fat distribution.
Wake time
Calculate a wake time that follows complete 90-minute sleep cycles.
Walking calories
Estimate calories burned walking from pace, time and body weight.
Water goal by activity
Adjust a daily fluid target for body weight, exercise and climate.
Weight loss timeline
Estimate how long a daily calorie deficit needs to reach a target weight.
Hiking time
Estimate hiking time from distance, elevation gain and pace using Naismith’s rule.
Cycling speed
Find average cycling speed and pace from distance and elapsed time.
Swimming pace
Convert swim distance and time into pace per 100 m or 100 yd.
1RM percentage table
Estimate a one-rep max and list training loads at common percentages.
MET calories
Estimate calories burned from an activity’s MET value, body weight and time.
Running distance
Work out running distance from average pace and elapsed time.
Running finish time
Predict a running finish time from pace and race distance.
Split times
Generate even race splits from a target time and distance.
Steps to calories
Convert a daily step count into distance, walking time and estimated calories.
Treadmill pace
Convert treadmill speed and incline into an equivalent flat pace.
Calorie Calculator - Estimate Daily Calories and TDEE
Find your daily calorie needs for maintenance, weight loss, or muscle gain based on activity level, age, height, and weight.
Body Fat Calculator - Estimate Body Fat Percentage Online
Estimate body fat percentage using proven body measurement formulas and get a quick read on body composition goals.
BMR Calculator - Estimate Basal Metabolic Rate Online
Calculate basal metabolic rate to estimate how many calories your body needs at rest before activity or exercise.
Ideal Weight Calculator - Find a Healthy Weight Range
Estimate a healthy weight range using popular medical formulas and compare results based on your height and sex.
Pregnancy Calculator - Estimate Due Date and Pregnancy Timeline
Calculate your due date, weeks of pregnancy, and trimester timeline from your last period or conception date.
Ovulation Calculator - Estimate Fertile Days and Ovulation
Predict your fertile window and likely ovulation date based on cycle timing to help with pregnancy planning.
Hydration deficit
Estimate fluid lost through sweating and the volume needed to replace it after exercise.
Pregnancy weight gain
Show the recommended weight-gain range for a singleton pregnancy from pre-pregnancy BMI.
Sun exposure time
Estimate how long untanned skin can stay in the sun before redness at a given UV index.
Body surface area
Calculate body surface area from height and weight using three common clinical formulas.
Fat-free mass index
Index lean body mass to height and compare it with typical FFMI bands.
Hat size from circumference
Convert head circumference into US, UK and EU hat sizes.
LDL estimate
Estimate LDL cholesterol from total cholesterol, HDL and triglycerides with the Friedewald equation.
Macro calories check
Check whether protein, carbohydrate and fat grams add up to the stated calories.
Menstrual period length
Measure bleeding days from period dates and estimate the next cycle and fertile window.
Ponderal index
Calculate weight relative to the cube of height and compare it with BMI.
Ring size from circumference
Convert finger circumference into US and EU ring sizes.
SPF reapply time
Get a practical reapplication interval from sunscreen strength, activity and water resistance.
Screen time
Add up daily screen exposure from work, phone, television and other devices.
Sleep efficiency
Compare actual sleep time with time spent in bed.
VO2 max estimate
Estimate cardiorespiratory fitness from age, sex and resting heart rate.
A1C to eAG
Convert an A1C percentage into estimated average glucose in mg/dL and mmol/L.
Alcohol calories
Estimate the calories in alcoholic drinks from volume, ABV and serving count.
Alcohol units
Convert drink volume and ABV into US standard drinks, UK units or Australian standard drinks.
BMI prime
Express BMI as a ratio to the upper healthy limit of 25.
Body frame size
Classify frame size as small, medium or large from height and wrist circumference.
Caffeine limit
Compare daily caffeine intake with general limits for adults, pregnancy and teenagers.
Calorie surplus
Set a daily calorie target for a chosen rate of weight gain.
Carb target
Turn daily calories into a carbohydrate gram target within the general intake range.
Cholesterol ratio
Calculate total cholesterol divided by HDL and the non-HDL value.
Fat target
Convert daily calories into a fat gram target within the general intake range.
Fiber target
Find a daily fiber recommendation from age, sex and calorie intake.
Protein per meal
Divide a daily protein target evenly across the meals you eat.
Resting heart rate
Compare a resting heart rate with age-based fitness context.
Sodium limit
Estimate a daily sodium ceiling based on age and health context.
Sugar limit
Set an added sugar limit from daily calories and current guidelines.
Swimming calories
Estimate calories burned swimming from stroke, time and body weight.
Weight gain timeline
Estimate how many weeks a steady calorie surplus needs to reach a target weight.
Ski calories
Estimate the calories burned during a skiing session from body weight, time and skiing style.
Training load
Estimate session and weekly training load from duration and perceived effort.
Jump rope calories
Estimate calories burned skipping rope from body weight, duration and intensity.
Race equivalence
Predict an equivalent race time at another distance using the Riegel formula.
Rest interval
Estimate recovery time between strength sets from load, goal and exercise type.
Rowing split
Convert rowing distance and time into a split per 500 m and related pace metrics.
Trail elevation
Measure elevation gain per kilometre and average grade for a trail route.
Triathlon time
Combine swim, bike, run and transition estimates into a total triathlon time.
VO2 max
Estimate cardiorespiratory fitness from resting and maximum heart rate.
Workout volume
Calculate total weight lifted from load, reps and sets, including weekly tonnage.
Yoga calories
Estimate calories burned in a yoga session by style, body weight and duration.
Frequently asked questions
How do I calculate my daily calorie needs?
Use our Calorie Calculator to find your TDEE based on your age, weight, height, and activity level.
Is BMI a good indicator of health?
BMI is a useful screening tool, but it's best used alongside other metrics like Body Fat percentage and waist circumference.
Are these health calculators medically approved?
These tools use standard medical formulas but should remain informational. Always consult a healthcare professional for medical advice.