— INTERACTIVE TOOLS
Free biology calculators.
Pregnancy, genetics, fetal development, biological age — a growing suite of research-grade calculators that answer specific questions in developmental biology and health. Each tool is free, private (nothing stored on our servers), and backed by the same deep research as our pillar articles.
— PREGNANCY & BABY
8 tools for the pregnancy journey
From trying to conceive through the first years of parenting — calculators grounded in developmental biology and backed by current obstetric guidelines.
Pregnancy Calculator
Calculate your due date, how many weeks pregnant you are, your trimester, and your conception date using LMP, ultrasound, or IVF dates.
Open calculator → LIVEOvulation Calculator
Find your fertile window and ovulation date based on your menstrual cycle length. Includes conception probability by day.
Open calculator →Contraction Timer
Time your contractions during labor. Automatically tracks duration, frequency, and pattern to help you decide when to go to the hospital.
Launching soonKick Counter
Track baby movements in the third trimester with a session timer and history. Early detection of changes in fetal activity.
Launching soonPregnancy Weight Gain Calculator
Track healthy weight gain throughout pregnancy based on your pre-pregnancy BMI and current week, with ACOG guidelines.
Launching soonBaby Growth Percentile Calculator
Calculate your baby’s weight, height, and head circumference percentile using WHO growth standards.
Launching soonBaby Eye Color Predictor
Estimate the probability of your baby’s eye color based on both parents’ eye colors, using current genetics research.
Launching soonChild Height Predictor
Estimate your child’s adult height using parent heights, current height, and age — the mid-parent and Khamis-Roche methods.
Launching soon— GENETICS
Visualize inheritance
Tools that turn the abstract rules of genetics into visual, interactive answers.
— HEALTH & LONGEVITY
Understand how your body is aging
Science-backed tools that estimate biological age and other health markers from lifestyle inputs.
Biological Age Calculator
Estimate how old your body actually acts versus your calendar age, based on lifestyle, fitness, and health markers.
Launching soonResearch-grade
Every calculation uses the formulas obstetricians, geneticists, and biologists actually use. Each tool is paired with a deep-dive article that explains the science.
Private by default
All calculations run in your browser. Nothing you enter is sent to our servers, stored, or shared. Your dates stay with you.
Always free
No sign-up required. No premium tier. No paywalls. Just useful calculators backed by careful research.