Due Date Calculator

Calculate your estimated due date and track your pregnancy timeline using multiple methods including LMP, conception date, ultrasound, or IVF transfer date.

Enter the first day of your last menstrual period
Most women have cycles between 21-35 days

About Due Date Calculation

Due dates are calculated based on a standard 280-day (40-week) pregnancy from the last menstrual period. However, only about 5% of babies are born exactly on their due date.

Calculation Methods:

  • LMP Method: Adds 280 days (40 weeks) to the first day of your last period
  • Conception Date: Adds 266 days (38 weeks) to the conception date
  • Ultrasound: Uses fetal measurements to estimate gestational age
  • IVF: Uses transfer date and embryo age for precise calculation

Pregnancy Trimesters:

  • First Trimester: Weeks 1-12
  • Second Trimester: Weeks 13-27
  • Third Trimester: Weeks 28-40+

Term Classifications:

  • Early Term: 37-38 weeks
  • Full Term: 39-40 weeks
  • Late Term: 41 weeks
  • Post Term: 42+ weeks

Note: These calculations provide estimates. Your healthcare provider may adjust your due date based on ultrasound measurements and other factors.