Conception Calculator
Estimate the likely conception date from your due date or last period.
Working backward from a due date or last period, this estimates the likely conception window — a rough range rather than a single exact date, since ovulation timing varies.
Why this gives a window, not a single day
Conception can only happen within a narrow fertile window around ovulation, but exact ovulation timing varies by individual and cycle — this estimate reflects typical timing, not a certainty for any specific cycle.
Frequently asked questions
How accurate is this estimate?
It's a reasonable estimate based on average cycle timing, but individual variation means the actual date could fall a few days outside the estimated window.
Why would I need to know my conception date?
It's sometimes used for medical or legal documentation purposes, or simply out of curiosity about pregnancy timing.