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Home/Health & fitness

HEALTH & WELLBEING

Health and fitness calculators

Free health calculators for BMI, body fat, daily calories, water intake, running pace and sleep cycles. Each page explains its method, inputs and limits.

39 tools to exploreCHOOSE YOUR STARTING POINT

BMI calculatorEssentialBMI calculator for adults: work out your body mass index from height and weight in metric or imperial units, with the NHS weight category and healthy range.Calorie calculatorCalorie calculator: estimate how many calories you need a day to maintain, lose or gain weight from your age, sex, height, weight and activity level.Pregnancy due date & gestational weeks calculatorCalculate your estimated due date, gestational age in weeks and days, trimester dates, and key developmental milestones.Ovulation & fertile window calculatorCalculate your exact ovulation day, 6-day fertile window, and peak conception days based on your menstrual cycle length.Pace calculatorPace calculator: work out your running pace per kilometre and per mile and your average speed from any distance and finish time.ACOG fertile window & conception calculatorIdentify peak fertile days and ovulation timing compliant with ACOG and ASRM clinical fertility guidelines for the US.ACOG pregnancy due date & trimester calculatorCalculate your estimated delivery date (EDD) and clinical trimester milestones adhering to ACOG and CDC gestational standards.NHS fertile window & ovulation calculatorCalculate your fertile window and ovulation dates aligned with UK NHS conception guidance and NICE fertility referral pathways.Sleep calculatorSleep calculator: find the best time to go to bed so you wake at the end of a 90-minute sleep cycle, based on when you need to get up.NHS pregnancy due date & scan calculatorCalculate your NHS pregnancy due date, 12-week dating scan window, 20-week anomaly scan, and UK Statutory Maternity Leave start dates.ACOG menstrual cycle predictorForecast upcoming period dates and evaluate cycle regularity according to ACOG abnormal uterine bleeding criteria.Body fat calculatorBody fat calculator: estimate your body fat percentage, fat mass and lean mass from your height, weight and tape-measure readings using the US Navy method.Menstrual cycle & period predictorPredict your next period date and the start of your next three cycles, and track your cycle regularity and phases.NHS menstrual cycle & period trackerPredict your next period and track menstrual cycle health compliant with UK NHS guidelines on cycle regularity and menorrhagia.US conception date & intercourse window calculatorFind your estimated date of conception and probable intercourse window derived from ACOG clinical due date standards.ACOG / IOM pregnancy weight gain calculatorCalculate recommended pregnancy weight gain in pounds by trimester compliant with ACOG and Institute of Medicine standards.Food calorie calculatorFind food calories and nutrition from USDA records, build a meal or recipe, convert portion weights and estimate totals per serving.Conception date & fertile window calculatorCalculate estimated date of conception and probable intercourse window from your estimated due date or last menstrual period.SART & ASRM IVF due date calculatorCalculate delivery date and gestational age after Day 3/5/6 blastocyst transfer according to SART and ASRM assisted reproduction standards.FDA & ACOG pregnancy test accuracy calculatorDetermine optimal over-the-counter pregnancy test timing based on FDA clearance standards and hCG doubling curves in the US.Chinese lunar baby gender prediction calculatorConsult the traditional Qing Dynasty lunar gender calendar based on maternal age and conception month, with modern genetic context.IVF embryo transfer due date calculatorCalculate exact delivery date and gestational age after Day 3, Day 5, or Day 6 frozen embryo transfer (FET) or egg retrieval.UK conception date & fertile intercourse calculatorCalculate your probable conception date and fertile window in the UK, reverse-engineered from your NHS 12-week dating scan or due date.ACOG embryo implantation timeline calculatorDetermine your peak 8–10 DPO implantation dates and early pregnancy hormone timeline compliant with ACOG clinical guidelines.Body shape calculatorCompare bust, waist and hip measurements with published apparel shape rules. See the matching category, rule and proportions in centimetres or inches.UK HFEA IVF transfer due date calculatorCalculate your UK IVF due date from fresh or frozen embryo transfer compliant with HFEA guidelines and NHS maternity handover schedules.NHS pregnancy test timing calculatorFind out when to take a home pregnancy test for accurate results according to NHS guidelines and UK early detection test sensitivities.NICE & RCOG pregnancy weight trackerTrack UK pregnancy weight gain in stones, pounds, and kilograms aligned with NICE antenatal guidelines and RCOG recommendations.ACOG early pregnancy loss probability calculatorReview gestational week-by-week pregnancy viability statistics and ACOG clinical guidance for early pregnancy loss.UK implantation window & spotting calculatorCalculate embryo implantation dates and review UK NHS guidance on differentiating implantation spotting from an early period.The Menopause Society (NAMS) age predictorEstimate your natural menopause age and stage transitions compliant with The Menopause Society (NAMS) STRAW+10 criteria.Healthy pregnancy weight gain & BMI calculatorTrack recommended gestational weight gain ranges and weekly progress based on pre-pregnancy BMI and Institute of Medicine guidelines.UK pregnancy reassurance & EPAU support calculatorCalculate week-by-week pregnancy continuation statistics and find UK NHS Early Pregnancy Assessment Unit (EPAU) and Tommy’s resources.NICE NG23 perimenopause & menopause predictorEstimate your menopause age and review clinical symptom management aligned with UK NHS standards and NICE guideline NG23.Menopause age & perimenopause predictorPredict your estimated age at natural menopause and perimenopause onset window based on maternal genetics, lifestyle, and menstrual history.Home pregnancy test timing & accuracy calculatorCalculate the earliest and most accurate dates to take a home pregnancy test based on ovulation, missed period dates, and test sensitivity.Early pregnancy miscarriage risk decay calculatorReview evidence-based statistical probabilities of a healthy ongoing pregnancy day by day and week by week based on clinical cohort studies.Water intake calculatorWater intake calculator: estimate how much water to drink each day based on European Food Safety Authority guidance, including in pregnancy and breastfeeding.Embryo implantation date & window calculatorCalculate your 6–12 DPO embryo implantation window, peak implantation date, and earliest detectable urine hCG dates.

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Planned health and fitness calculators

Calculators we're building next in this category.

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35Condom size calculatorPlanned
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38Caffeine calculatorPlanned
39Carb calculatorPlanned

CALCULATOR INPUTS AND METHODS

Health calculator inputs and methods

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