Calculate your estimated due date from your last period or conception date. Shows weeks pregnant and days to go.
A full-term pregnancy lasts approximately 40 weeks (280 days) from the first day of your last menstrual period. This is Naegele's Rule — the standard method used worldwide by obstetricians and midwives.
The due date is an estimate. Most babies are born within two weeks either side (between 38 and 42 weeks). Birth before 37 weeks is premature; after 42 weeks is post-term.
Your healthcare provider will confirm your due date via an ultrasound scan, usually performed between 8 and 13 weeks. This is more accurate than date-based calculation alone.