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Ovulation Calculator

Find your fertile window and ovulation date.

Details

Results

Estimated ovulation -
Fertile window -
Most fertile days -
Next period -

Estimates only - not medical advice.

How it works

Ovulation typically occurs about 14 days before your next period, so we count back from your expected next period (based on cycle length). The fertile window spans the five days before ovulation through the day after.

Best timing: the two days before ovulation are usually the most fertile.

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Good to know

FAQs

When do I ovulate?

Usually about 14 days before your next period; for a 28-day cycle that’s around day 14.

What is the fertile window?

The roughly 6 days ending on ovulation day, when conception is most likely.

How accurate is this?

It’s an estimate based on average timing; ovulation predictor kits and tracking add precision.

Does cycle length matter?

Yes - enter your average cycle length for a better estimate.

Is this medical advice?

No - talk to your doctor about fertility and conception.