Health and Fitness

Calculators for tracking health and well-being.

Energy Availability Calculator

Estimate energy availability from intake, exercise expenditure, body weight, body fat percentage, and a target availability level.

Race Fueling Plan Calculator

Plan carbohydrate, fluid, sodium, and gel needs for an endurance race using hourly targets and event duration.

Sleep Efficiency and Recovery Calculator

Estimate sleep efficiency, resting-heart-rate drift, and a simple recovery score from time in bed, sleep time, awakenings, and baseline pulse.

Training Monotony and Strain Calculator

Analyze seven days of training load to estimate weekly load, daily variation, monotony, and strain.

Body Composition Goal Calculator

Estimate target body weight and weeks needed for a body-fat goal while accounting for planned lean-mass change.

Cycling Power Zones Calculator

Estimate normalized power, training stress, watts per kilogram, and cadence-adjusted torque from FTP and workout intensity.

Running Critical Speed Calculator

Estimate critical speed, anaerobic distance reserve, target time, and target pace from two race or time-trial performances.

Heat Strain Training Calculator

Estimate apparent temperature, heat strain score, fluid need, and adjusted training duration from temperature, humidity, pace, and acclimation.

Protein Distribution Calculator

Split a daily protein target across meals and estimate leucine per meal against a practical leucine threshold.

Recovery Carb Refill Calculator

Estimate carbohydrate refill needs after a session using body weight, duration, intensity, recovery window, and hourly intake rate.

Lactate Threshold Pace Calculator

Lactate Threshold Pace Calculator estimates endurance load, energy cost, hydration need, and environmental adjustment.

Altitude Pace Adjustment Calculator

Altitude Pace Adjustment Calculator estimates endurance load, energy cost, hydration need, and environmental adjustment.

Heat Training Risk Calculator

Heat Training Risk Calculator estimates endurance load, energy cost, hydration need, and environmental adjustment.

Marathon Fueling Calculator

Marathon Fueling Calculator estimates endurance load, energy cost, hydration need, and environmental adjustment.

Critical Power Calculator

Critical Power Calculator combines load, repetitions, sets, weekly frequency, and recovery into strength and volume metrics.

Power-to-Weight Calculator

Power-to-Weight Calculator combines load, repetitions, sets, weekly frequency, and recovery into strength and volume metrics.

Strength Volume Tonnage Calculator

Strength Volume Tonnage Calculator combines load, repetitions, sets, weekly frequency, and recovery into strength and volume metrics.

Wilks-Style Strength Score Calculator

Wilks-Style Strength Score Calculator combines load, repetitions, sets, weekly frequency, and recovery into strength and volume metrics.

Protein Periodization Calculator

Protein Periodization Calculator converts body mass, training volume, calories, and macro targets into daily nutrition numbers.

Glycogen Storage Calculator

Glycogen Storage Calculator converts body mass, training volume, calories, and macro targets into daily nutrition numbers.

Marathon Carb Load Calculator

Marathon Carb Load Calculator converts body mass, training volume, calories, and macro targets into daily nutrition numbers.

Body Recomposition Macro Calculator

Body Recomposition Macro Calculator converts body mass, training volume, calories, and macro targets into daily nutrition numbers.

Injury Risk Load Ratio Calculator

Injury Risk Load Ratio Calculator blends sleep, HRV, soreness, stress, heart rate, and training load into a readiness estimate.

HRV Readiness Calculator

HRV Readiness Calculator blends sleep, HRV, soreness, stress, heart rate, and training load into a readiness estimate.

Sleep Debt Performance Calculator

Sleep Debt Performance Calculator blends sleep, HRV, soreness, stress, heart rate, and training load into a readiness estimate.

Taper Volume Calculator

Taper Volume Calculator blends sleep, HRV, soreness, stress, heart rate, and training load into a readiness estimate.

FFMI Calculator

FFMI Calculator estimates body-composition direction, daily energy target, and timeline from anthropometric inputs.

Body Fat Change Timeline Calculator

Body Fat Change Timeline Calculator estimates body-composition direction, daily energy target, and timeline from anthropometric inputs.

Zone 2 Volume Calculator

Zone 2 Volume Calculator estimates body-composition direction, daily energy target, and timeline from anthropometric inputs.

Race Split Planner

Race Split Planner estimates body-composition direction, daily energy target, and timeline from anthropometric inputs.

Training Load Calculator

Estimate heart-rate based training load using duration, resting heart rate, max heart rate, and average heart rate.

Cooper Test VO2 Max Calculator

Estimate VO2 max from the distance covered during a 12-minute Cooper test.

Race Time Predictor

Predict a target race time from a recent performance using the Riegel endurance model.

Body Roundness Index Calculator

Estimate Body Roundness Index from waist circumference and height.

Relative Strength Calculator

Estimate one-rep max and relative strength from lifted weight, reps, and body weight.

Calorie Cycling Calculator

Plan high- and low-calorie days while preserving a weekly calorie target.

Sweat Rate Calculator

Estimate sweat rate from body weight change, fluid intake, urine, and exercise duration.

Running VO2 Cost Calculator

Estimate oxygen demand and calories from running pace, grade, and body weight.

Metabolic Age Estimator

Compare measured BMR with expected BMR and estimate a simple metabolic-age signal.

Hydration Sodium Calculator

Estimate fluid and sodium replacement from sweat rate, duration, sodium concentration, and replacement target.

Recovery Carb Load Calculator

Estimate post-training carbohydrate needs from body weight, training time, and grams per kilogram per hour.

TDEE Calculator

Estimate daily maintenance calories from BMR and activity multiplier.

Protein Intake Calculator

Estimate daily protein target from body weight and grams per kilogram.

Carbohydrate Intake Calculator

Calculate carbohydrate grams from calories and target carbohydrate share.

Fat Intake Calculator

Calculate daily fat grams from calories and target fat percentage.

Heart Rate Zones Calculator

Estimate training zones from maximum heart rate and selected intensity range.

Sleep Cycle Calculator

Estimate sleep time from cycle length, number of cycles, and time to fall asleep.

Walking Calories Calculator

Estimate calories burned while walking from body weight, distance, and grade.

Cycling Calories Calculator

Estimate cycling calories from body weight, duration, and MET intensity.

Workout Hydration Calculator

Estimate fluid needs from workout duration, sweat rate, and fluid already consumed.

Pace to Speed Calculator

Convert running pace in minutes per kilometre to speed and race time.

BMI Prime Calculator

Compare BMI with the common upper reference value of 25 using BMI Prime.

Lean Body Mass Calculator

Estimate lean body mass from weight and body fat percentage.

Maximum Heart Rate Calculator

Estimate maximum heart rate with common age-based formulas.

VO2 Max Pace Estimator

Estimate oxygen cost and VO2 demand from running speed.

Water Intake Calculator

Estimate daily water needs from body weight, activity time, and extra climate allowance.

Macro Calculator

Convert calorie targets and macro percentages into grams of protein, carbohydrate, and fat.

One-Rep Max Calculator

Estimate one-repetition maximum strength from a lifted weight and repetitions completed.

Running Pace Calculator

Calculate pace, speed, total time, and marathon projection from distance and finish time.

Target Heart Rate Calculator

Estimate training heart rate from age, resting heart rate, and desired intensity.

Waist-to-Hip Ratio Calculator

Calculate waist-to-hip and waist-to-height ratios from simple body measurements.

Body Surface Area Calculator

Estimate body surface area with Mosteller, Du Bois, and Haycock formulas.

Steps to Calories Calculator

Estimate walking distance, calories, and time from step count, stride length, and body weight.

BMI Calculator

Calculate your Body Mass Index and check your weight category.

BMR and TDEE Calculator

Calculate your Basal Metabolic Rate and Total Daily Energy Expenditure using Mifflin-St Jeor and Harris-Benedict formulas.

Calorie Deficit & Weight Loss Time Calculator

Calculate how long it will take to reach your weight goal based on your calorie deficit. See visual predictions and graphs.

Body Fat Percentage (Deurenberg)

Calculate your body fat using BMI - simple method.

Body Fat Percentage (US Navy)

Calculate your body fat accurately using circumference measurements - more reliable method.

Pregnancy Calculator

Estimate your due date, gestational age, and upcoming appointments with three calculation methods.

Ovulation & Fertility Calculator

Estimate your next ovulation, fertile window, and upcoming period dates.

BAC Calculator - Blood Alcohol Content

Calculate estimated blood alcohol level, drinking window, and time until sober.

Ideal Weight Calculator

Calculate your ideal weight using three different formulas (Devine, Robinson, Hamwi).