Side-by-side comparison helps you choose the right calculator for a specific clinical question.
Obstetrics
Estimate your conception date from your last menstrual period and cycle length, or from your estimated due date. Includes likely conception window and ovulation estimate.
Formula
Conception estimate ≈ EDD - 266 days, or LMP + cycle length - 14 days
Inputs
Obstetrics
Estimate your ovulation date and fertile window using cycle length and last period date. See best days to conceive and estimated due date if conception occurs.
Formula
Estimated ovulation date = projected next period - 14 days
Inputs