Pregnancy due date calculator
Estimate your due date from the first day of your last period.
About this calculator
The due date is counted as 280 days, or 40 weeks, from the first day of your last period, adjusted if your cycle is longer or shorter than 28 days. The calculator also estimates conception and the end of the first trimester.
Only a small share of babies arrive on the day. Your midwife or doctor will confirm your dates, often with a scan.
Common questions
What if my cycle is not 28 days?
Enter your usual cycle length and the date is adjusted.
Is a scan more accurate?
Yes. A dating scan can refine the date.
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