Every calculator you'll need — free.
Join Belly Weekly and unlock all 21 calculators free — from ovulation and due dates to gestational age, weight gain and fun gender predictors.
Free forever. No spam — just your weekly pregnancy update. Unsubscribe anytime.
Conception, Cycle & Gender
Ovulation & Fertility Calendar
Free ✦Map your fertile window and best days to try.
Fertile Days & Ovulation
Free ✦Your most fertile days, on a calendar.
Safe Days Calendar
Free ✦See your lower-chance days across your cycle.
Date of Conception
Free ✦Estimate when conception likely happened.
Chinese Baby Gender
Free ✦The classic Chinese gender chart — just for fun.
Gender by Parent Blood Type
Free ✦Predict baby's gender from blood types.
Gender by Rh Factor
Free ✦Gender prediction from parents' Rh factor.
Gender by Blood Renewal
Free ✦The blood-renewal method prediction.
Pregnancy Tracking & Health
Pregnancy Due Date
Free ✦Your estimated due date from your last period.
How Many Weeks Pregnant
Free ✦Exactly how far along you are, today.
Pregnancy By Week
Free ✦What's happening this week, for you and baby.
Gestational Age (AOG)
Free ✦Calculate gestational age from your dates.
Weekly Pregnancy Weight Gain
Free ✦Healthy weight-gain targets, week by week.
Gestational Diabetes Diet
Free ✦Plan balanced meals if you're managing GD.
Crown-Rump Length (CRL)
Free ✦Estimate gestation from CRL measurements.
Ultrasound Gestation Period
Free ✦Date the pregnancy from ultrasound data.
Baby & Newborn
Baby Eye Color
Free ✦A fun guess at baby's eye color from parents'.
Infant Nutrition Needs (Under 1)
Free ✦Daily nutrition guidance for baby's first year.
Infant Feeding Volume
Free ✦How much milk baby needs per feed, by weight.
Child Development Tracker
Free ✦Milestones to watch for, month by month.
Child Height & Weight
Free ✦See how baby's growth tracks on the charts.