Fitness and Health Calculators

Fertility Calculator

Estimate fertile days, ovulation timing, peak fertility dates, and the next period from your cycle pattern.

Calculator

Enter your values and view the result instantly.

Change any field below to update the answer straight away.

11 Mar 2026

Estimated ovulation day

6 Mar 2026

Fertile window starts

12 Mar 2026

Fertile window ends

10 Mar 2026

Peak fertility starts

11 Mar 2026

Peak fertility ends

Day 11

Current cycle day

25 Mar 2026

Estimated next period

Related

More from the same category

If you are comparing options or checking related figures, these calculators may help.

Ovulation Calculator

Estimate ovulation, fertile days, and the next period date from your cycle length and luteal phase settings.

Due Date Calculator

Estimate your pregnancy due date from your last period or conception date, with gestational age and trimester timing.

Pregnancy Weeks Calculator

Calculate how many weeks pregnant you are from your last period or due date, with trimester and weeks-remaining estimates.

BMI Calculator

Check body mass index with metric or imperial units and compare the result with standard adult BMI ranges.

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