11 free tools · No account required
Free Health, Fitness & Pregnancy Calculators
Explore estimated dates, energy needs, body measurements and training pace using the method explained beside each calculator. Inputs are processed locally. Results depend on assumptions and individual circumstances; they support planning and do not replace personal clinical guidance.
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Ovulation & Fertile Window Calculator
Estimate cycle dates from your last period and average cycle length. Calendar estimates cannot confirm ovulation or prevent pregnancy.
Open tool →Menstrual Period & Cycle Predictor
Plan approximate upcoming period dates from your cycle history, with clear limits for irregular cycles and long-range predictions.
Open tool →Pregnancy Due Date & Milestone Calculator
Estimate a due date and gestational age using a last period, estimated conception date, or IVF embryo transfer date.
Open tool →Child Height Predictor (Based on Parents)
Explore a rough adult height estimate using parental measurements. Family averages cannot predict an individual child’s growth precisely.
Open tool →90-Minute Sleep Cycle & Smart Alarm Calculator
Compare bedtime and wake-up options using a simplified cycle interval and your estimated time to fall asleep.
Open tool →Reverse Conception Date & Fertile Window Calculator
Work backward from pregnancy dating to explore an approximate conception window, with uncertainty explained.
Open tool →U.S. Navy Body Fat Percentage Calculator
Estimate adult body fat from circumference measurements and compare the result with its measurement limitations.
Open tool →TDEE & Calorie Deficit Target Calculator
Estimate resting energy needs and daily expenditure from body measurements and an activity multiplier.
Open tool →Child Blood Type & Eye Color Genetic Predictor
Explore a simplified inheritance model. Displayed percentages are illustrative assumptions, not personalized genetic predictions.
Open tool →Caffeine Half-Life & Bedtime Cutoff Calculator
Model the approximate caffeine remaining after one serving using an adjustable half-life and bedtime.
Open tool →Running Pace Calculator
Calculate running pace from distance and elapsed minutes. See minutes per kilometer, minutes per mile, and average speed in km/h together.
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Which health & wellness tool should I use?
Pregnancy and cycle dates
Use the correct starting date and cycle length. For IVF, distinguish embryo age at transfer from time in frozen storage; confirm pregnancy dating with your care team.
Nutrition and body estimates
Compare the selected formula and measurement method before interpreting calorie or body-fat estimates. Repeated measurements are most useful when taken consistently.
Sleep and exercise planning
Convert a run into pace or explore a bedtime estimate. Sleep cycles and recovery needs vary, so a calculated schedule is a starting point rather than a guarantee.