Calculator tool
The calculator follows common due-date assumptions: LMP plus 280 days, conception plus 266 days, ultrasound scan date adjusted by measured gestational age, or IVF transfer date plus 266 days minus embryo age.
Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.
What method is most accurate?
Early ultrasound and IVF transfer dating are usually more precise. LMP estimates assume cycle timing and ovulation are close to average.
Is the due date exact?
No. Due dates are planning estimates. Actual delivery can occur before or after the estimated date.
Pregnancy Calculator
Estimate current pregnancy week, due date, trimester, and milestone dates from LMP, due date, conception, ultrasound, or IVF transfer.
Open toolConception Calculator
Estimate when conception likely occurred from an estimated due date, last menstrual period, or ultrasound dating.
Open toolOvulation Calculator
Estimate your ovulation date and 6-day fertile window based on your last period and average cycle length.
Open tool