Pregnancy Due Date Calculator

Estimate your baby's due date and track your gestational progress across all three trimesters from your last period, conception, or IVF date.

Gestational journey, trimesters & due date.

Calculate my due date using

First day of your last period

Average Cycle Length (days)

days

Estimated due date

Gestational age counts from the first day of your last period — two weeks before conception. Your provider may adjust your due date at your first ultrasound.

Worked Example — LMP of January 1, 2026

Due October 8, 2026280 days from LMP (28-day cycle) — 29w 0d pregnant and in the 3rd trimester as of July 23, 2026

Common Mistakes to Avoid

Only about 5% of babies are born on their exact due date. This is a helpful estimate based on averages, not a guarantee. An ultrasound in the first trimester is considered the most accurate way to date a pregnancy — always confirm your estimate with your doctor.
This isn't medical advice — it's a scheduling estimate. Use this to get a general sense of timing and gestational age, not to make clinical decisions. Your doctor's dating (especially from an early ultrasound) takes precedence over this calculator's estimate.