Free Pregnancy Calculator 2026 to calculate your due date, pregnancy week, conception date and full pregnancy timeline based on LMP or conception date.
Find your estimated due date and pregnancy progress easily
This pregnancy calculator estimates your due date based on the first day of your last menstrual period (LMP) or conception date. The calculation assumes a typical pregnancy duration of 280 days (40 weeks) from the LMP. Keep in mind that only about 5% of babies are born on their exact due date, so this is an estimate. Your healthcare provider may adjust your due date based on ultrasound measurements.
Important: This calculator provides estimates for educational purposes only. Every pregnancy is unique. Always consult with your healthcare provider for personalized medical advice, accurate due date determination, and prenatal care guidance.
Due dates are estimates based on a 40-week pregnancy. Only about 5% of babies are born on their exact due date, with most arriving within two weeks before or after.
You can use your conception date or an ultrasound-determined due date. Early ultrasounds are the most accurate way to date a pregnancy.
First trimester: weeks 1-12, Second trimester: weeks 13-26, Third trimester: weeks 27-40.
Your healthcare provider may adjust your due date based on ultrasound measurements, especially if done in the first trimester.