Ovulation Calculator

Calculate ovulation instantly with our free Ovulation Calculator. Trusted formulas, instant results, no sign-up required.

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How the Ovulation Calculator Is Calculated

Estimated ovulation day is calculated by counting back 14 days from the end of your cycle (cycle length minus 14 days after your last period started) — the luteal phase length is relatively consistent even when cycle length varies, which is why this method is used instead of counting forward from day one.

About the Ovulation Calculator

Calculate ovulation instantly with our free Ovulation Calculator. Trusted formulas, instant results, no sign-up required.