How to use the Pregnancy Due Date Calculator
Fill in the fields on the left. Results, charts and the breakdown update instantly as you type or move a slider. Pick your country at the top of the page to switch currency.
Formula
Due date = first day of last period + 280 days (+ cycle length − 28)
Frequently asked questions
How accurate is the due date?
It is an estimate — most babies arrive between 38 and 42 weeks. An early ultrasound gives the most accurate date.
Results are estimates for information only and are not financial, tax or legal advice. Tax rules, interest rates and fees change, so confirm important numbers with your bank, employer or a qualified adviser. Read our disclaimer.