Free tools
47 calculators and timers for your cycle, pregnancy, training and sleep. Each one shows the formula it uses and where that formula comes from. No sign-up, and what you enter never leaves your browser.
Apps and privacy
Check an app before you trust it with your data or your money.
- App Privacy CheckerPick a period, pregnancy or wellness app and see what its own policy says about selling data, ads, accounts and deletion, with the quoted passage.
- App Subscription Cost CalculatorAdd your app subscriptions with their price and billing period to see the total per month, per year and over 5 years, plus monthly vs yearly plans.
Period and cycle
Work out dates in your cycle.
- Cycle Length CalculatorEnter the start dates of your last 3 to 6 periods to get your average cycle length, your shortest and longest cycle, and how much they vary.
- Ovulation CalculatorEnter the first day of your last period and your cycle length to estimate your ovulation day, your 6-day fertile window and your next 3 cycles.
- Period CalculatorEnter the first day of your last period, your cycle length and your period length to see when your next 6 periods are likely to start and end.
- When to Take a Pregnancy Test CalculatorEnter the first day of your last period and your cycle length to see the earliest reliable day for a home pregnancy test and when to test again.
Pregnancy
Dates and numbers for pregnancy.
- Conception Date CalculatorEnter your due date, or your last period and cycle length, to get the most likely conception date and the range of days it could have been.
- Due Date CalculatorEnter the first day of your last period and your cycle length to get an estimated due date, how far along you are and your trimester dates.
- hCG Doubling Time CalculatorEnter two hCG blood test results and when they were taken to get the doubling time in hours, the percentage change and the rise per 48 hours.
- IVF Due Date CalculatorEnter your embryo transfer, egg retrieval or IUI date to get your IVF due date, how many weeks pregnant you are today and your trimester dates.
- Pregnancy Week CalculatorEnter the first day of your last period or your due date to see how many weeks and days pregnant you are today, your trimester and days to go.
- Pregnancy Weight Gain CalculatorEnter your pre-pregnancy weight, height and week of pregnancy to see the guideline weight gain range at term and at your current week.
Labour and baby
Timers and counters for the last weeks and the first months.
- Baby Age CalculatorEnter your baby's date of birth to get their age in weeks, months and days. Add the due date to get the corrected age for a premature baby.
- Contraction TimerTap when a contraction starts and ends to see how long each one lasts, how far apart they are and your averages for the last hour.
- Kick CounterTap each time your baby moves to see the count, the time since the first movement and how long it took to reach 10 movements.
Fitness and body
Training and nutrition numbers.
- BMI Calculator for WomenEnter your height and weight in metric or US units to get your BMI, the WHO category and the weight range WHO classes as healthy for your height.
- Body Fat Calculator for WomenEnter your height, neck, waist and hip measurements to estimate body fat percentage with the US Navy method. Add your weight to see fat and lean mass.
- Calorie Calculator for WomenEnter your age, height, weight and activity level to estimate your daily maintenance calories (TDEE) and your BMR with the Mifflin-St Jeor equation.
- Heart Rate Zone Calculator for WomenEnter your age and, if you know it, your resting heart rate to get your estimated maximum heart rate and five training zones in beats per minute.
- Macro CalculatorEnter your daily calories and pick a split to get grams of carbohydrate, protein and fat per day and per meal, with a check against the AMDR ranges.
- One Rep Max Calculator (1RM)Enter the weight you lifted and how many reps you did to get your estimated one rep max and training weights from 60% to 95%, in kg or lb.
- Protein Intake Calculator for WomenEnter your body weight and how active you are to get a daily protein range in grams, plus how much that is per meal across 3 or 4 meals.
- Running Pace CalculatorEnter a distance and finish time to get your pace per km and per mile, speed and even splits. Or enter a pace to get your finish time.
Skincare, hair and nails
Quizzes, checkers and calculators for skin, hair, nails and sizing.
- Bra Size CalculatorEnter your underbust and bust measurements in inches or centimetres to get a starting bra size in US, UK and EU sizing, plus your sister sizes.
- Can I Mix These? Skincare Ingredient CheckerPick two skincare ingredients, such as retinol and vitamin C, to see if they are fine together, better at different times, or need care, and why.
- Hair Developer CalculatorEnter how much hair colour or bleach you have and the mixing ratio on the box to get the amount of developer and the total mix in g, ml or oz.
- Hair Growth CalculatorEnter your hair length now, your goal length and any planned trims to see how many months it may take and an estimated date, with a range.
- Hair Porosity QuizAnswer 6 questions about how your hair gets wet, dries and takes products to see if it is likely low, medium or high porosity. No float test needed.
- Hair Type QuizAnswer 6 questions about how your hair dries with no product to get a likely curl pattern on the 1 to 4C chart: straight, wavy, curly or coily.
- Nail Salon Cost CalculatorEnter the price of a full set and a fill, how often you go and your tip to see what gel, acrylic or dip nails cost per month and per year.
- Nail Shape QuizAnswer 6 questions about your nail length, strength and how you use your hands to get a nail shape that fits your day, with a second choice.
- Press-On Nail Size CalculatorEnter the width of each nail in millimetres to get your press-on nail size from 0 to 9 for every finger, plus the closest XS, S, M or L set.
- Ring Size Converter and CalculatorEnter a ring's inner diameter, your finger's circumference in mm, or a size you know, to get your ring size in US, UK, EU and Japanese sizes.
- Skin Cycling SchedulePick a start date and a cycle to get a 4-week skin cycling calendar: which nights are for exfoliation, retinoid and recovery, with dates.
- Skin Type QuizAnswer 7 questions about shine, tightness, pores and how your skin reacts to products to get your likely skin type and whether it is also sensitive.
- Skin Undertone QuizAnswer 6 questions about your veins, jewellery, white fabric and foundation shades to find your likely undertone: warm, cool, neutral or olive.
- Skincare Expiry CheckerEnter the date you opened a product and the open-jar number on the pack (6M, 12M, 24M) to get its use-by date and how many days are left.
- Skincare Routine Order BuilderTick the skincare products you own to get the order to apply them, morning and night, with sunscreen last in the morning and retinoid at night.
- Sunscreen CalculatorPick the skin that is exposed and your hours outdoors to see how much sunscreen to apply, how often to reapply and how long a bottle lasts.
Clothes and style
Colour, sizing, wardrobe and packing.
- Capsule Wardrobe CalculatorEnter how many tops, bottoms, dresses, layers and shoes you own to see how many outfits they make, what to add next, or a starter plan.
- Packing List GeneratorEnter trip length, climate, trip type, laundry and bag size to get a tickable packing checklist with quantities. Copy it or print it.
- Seasonal Color Analysis QuizAnswer 8 questions about your veins, hair, eyes, contrast and the colours that suit you to get your likely season, sub-season and a colour palette.
- Women's Clothing Size ConverterConvert a women's dress or top size between US, UK, EU, Australian, Japanese and letter sizes, or enter bust, waist and hip to find your size.
Sleep and everyday
Small tools for rest, habits and routine.
- Box Breathing TimerChoose how many seconds per step and how many minutes, then press start. The timer guides you to breathe in, hold, breathe out and hold.
- Free Habit TrackerAdd up to 10 habits, pick a month and tick the days you do them. See each habit's streak and completion rate, or print a clean monthly grid.
- Sleep CalculatorEnter the time you need to wake up, or the time you are going to bed, to get bedtimes or wake-up times that fit 4, 5 or 6 sleep cycles.
- Water Intake Calculator for WomenChoose your life stage, add today's exercise and the weather, and get a daily fluid guide in litres, cups and fluid ounces.