All calculators
Every calculator is free, runs in your browser and explains the formula behind its answer.
Body
BMI, body fat, waist ratios and ideal weight.
BMI Calculator
Body Mass Index with healthy weight range and daily calories.
Open calculatorBody Fat Calculator
Estimate body fat % with the U.S. Navy circumference method.
Open calculatorLean Body Mass Calculator
Fat-free body mass estimate using the Boer equation.
Open calculatorBody Frame Size Calculator
Small, medium or large frame from height and wrist size.
Open calculatorIdeal Weight Calculator
Your healthy weight range from four medical formulas.
Open calculatorBMR Calculator
Calories your body burns at complete rest (Mifflin-St Jeor).
Open calculatorWaist-to-Hip Ratio Calculator
Abdominal obesity risk from the WHO 2008 waist-to-hip cut-offs.
Open calculatorWaist-to-Height Ratio Calculator
Keep your waist under half your height (NICE NG246).
Open calculatorNutrition
Calories, macros and daily hydration targets.
TDEE Calculator
Total daily energy expenditure with activity multipliers.
Open calculatorCalorie Calculator
Daily calories to maintain, lose or gain weight (TDEE).
Open calculatorMacro Calculator
Daily protein, carb and fat grams for your goal.
Open calculatorWater Intake Calculator
How much water to drink per day for your body and activity.
Open calculatorProtein Intake Calculator
Daily protein target from weight, training and goal.
Open calculatorTraining
Strength, pace, heart rate, sleep and calories burned.
One-Rep Max Calculator
Estimate your 1RM from any set — Epley & Brzycki.
Open calculatorPace Calculator
Convert distance and time into pace and speed.
Open calculatorHeart Rate Zone Calculator
Your five training zones from your age (Tanaka formula).
Open calculatorCalories Burned Calculator
Estimate calories burned per activity from Compendium MET values.
Open calculatorSleep Calculator
Ideal bedtimes and wake times from 90-minute sleep cycles.
Open calculatorWomen's Health
Ovulation, cycles, pregnancy dates and weight gain.
Ovulation Calculator
Predict ovulation day and your fertile window.
Open calculatorPeriod Calculator
Predict your next three period start dates.
Open calculatorDue Date Calculator
Estimate your pregnancy due date (Naegele’s rule).
Open calculatorPregnancy Weight Gain Calculator
IOM 2009 weight-gain ranges from your pre-pregnancy BMI.
Open calculatorPregnancy Calorie Calculator
Daily calorie needs by trimester
Open calculatorMenopause Age Estimator
Estimate your menopause age
Open calculatorPregnancy Weeks Calculator
How many weeks and days — and what is left.
Open calculatorBreastfeeding Calorie Calculator
Extra daily calories while breastfeeding.
Open calculatorIrregular Cycle Calculator
Next period range from your shortest and longest cycles.
Open calculatorBone Density / Osteoporosis Risk Screener
Risk-factor screener — not a diagnosis
Open calculatorIron Needs Calculator
Daily iron RDA by life stage
Open calculatorPCOS Symptom Screener
Symptom-pattern screener — not a diagnosis
Open calculatorPostpartum Recovery Timeline
A realistic, general timeline of physical recovery milestones
Open calculatorPerimenopause Symptom Screener
Checks how many common perimenopause symptoms you recognise — not a diagnosis
Open calculatorCycle Symptom Log
Track your flow, mood, energy and cramps day by day — no formula, just a private record you own. No formula — a personal log stored only in your browser.
Open the logBody Measurements Log
Keep a private, dated record of your weight, waist, hips and body fat % — and watch the trend lines, not single numbers. No formula — a personal log stored only in your browser.
Open the logBBT & Fertility Awareness Log
Record waking temperature and cervical mucus to observe your cycle patterns — for awareness only, not contraception. No formula — a personal log stored only in your browser.
Open the log