This interactive tool calculates your pregnancy due date, an estimate of when you are likely to deliver your baby.
To find your due date, the calculator takes the first day of your last menstrual period (LMP) and adds 40 weeks. If you are planning a pregnancy, you can use this calculator to plan the birth for a certain month or season.
Katz VL (2008). Prenatal care. In RS Gibbs et al., eds., Danforth's Obstetrics and Gynecology, 10th ed., p. 4. Philadelphia: Lippincott Williams and Wilkins.
Your due date is an estimate of when you will likely have your baby, based on the normal length of a full-term pregnancy. Most women deliver within 14 days of their due date.
Your health professional will also measure the size of your uterus and use ultrasound testing to determine your due date. For more information on planning a healthy pregnancy, see the topic Pregnancy.
Other Works Consulted
- Bernstein HB, Van Buren G (2013). Normal pregnancy and prenatal care. In AH DeCherney et al., eds., Current Diagnosis and Treatment Obstetrics and Gynecology, 11th ed., pp. 141–153. New York: McGraw-Hill.
- Katz VL (2008). Prenatal care. In RS Gibbs et al., eds., Danforth's Obstetrics and Gynecology, 10th ed., pp. 1–21. Philadelphia: Lippincott Williams and Wilkins.
Current as ofSeptember 5, 2018
Author: Healthwise Staff
Medical Review: Sarah A. Marshall, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
Kirtly Jones, MD - Obstetrics and Gynecology, Reproductive Endocrinology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2019 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Donations to UW Health are managed by the University of Wisconsin Foundation, a publicly supported charitable organization under 501(c)(3) of the Internal Revenue Code.