Before week 20, length is mainly shown from crown to rump. From week 20 onward, it is shown from head to heel.
Enter your dates
Pregnancy is counted from the first day of your last menstrual period.
Enter the first day of your last period to see your gestational age, trimester, estimated due date, and approximate baby development.
Calculate pregnancy weeksPregnancy is counted from the first day of your last menstrual period.
Along with gestational age, the calculator shows the pregnancy month, trimester, due date, approximate length, weight, size comparison, and weekly development.
Before week 20, length is mainly shown from crown to rump. From week 20 onward, it is shown from head to heel.
The displayed 10th-90th percentile range reflects natural variation and does not replace an ultrasound assessment.
Weekly illustrations from weeks 1-42 make changes easier to understand at a glance.
Move easily from cycle tracking to ovulation, gestational age, due date, conception date, and a week-by-week chart.
All results are estimates intended to provide a helpful overview. They do not replace an ultrasound, diagnosis, or medical advice. Length is shown around a weekly reference value. Weight ranges from week 22 use the 10th-90th percentiles from the INTERGROWTH-21st standard.
Choose a category and continue with the tool you need.
Choose a category