Calculate your estimated due date, gestational age, and pregnancy milestones.
Calculate your estimated due date using Naegele's rule. Enter the first day of your last menstrual period, conception date, or IVF transfer date to see when your baby is expected. This free due date calculator shows your gestational age in weeks and days, which trimester you are in, and key pregnancy milestones such as the end of the first trimester, anatomy scan, viability, and full term dates.
For the LMP method, the due date is calculated by adding 280 days (40 weeks) to the first day of your last menstrual period, adjusted for cycle length. If your cycle is longer or shorter than 28 days, the calculator adjusts accordingly. For the conception date method, 266 days are added to the date of conception. For IVF transfers, the calculator assumes a day-5 blastocyst transfer and adds 261 days from the transfer date.
Gestational age counts from the first day of the last menstrual period, even though conception typically occurs about two weeks later. A full-term pregnancy is 37 to 42 weeks. The trimester progress bar shows your progress through each of the three trimesters and the milestones timeline helps track important dates throughout pregnancy.