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Ovulation calculator

Find out which days you are most likely to get pregnant.

Count from the first day of one period to the first day of the next. Most cycles are 26–32 days. If you don't know, leave it at 28.

How it works

An egg is usually released about 14 days before your next period. Sperm can live for up to 5 days, so the most fertile time is the 5 days before ovulation and the day of ovulation.

Tips

  • Having sex every 2–3 days through the month covers your fertile days without needing exact timing.
  • Ovulation kits from a chemist can help confirm the day.
  • Try not to let timing become stressful. It is only one part of the picture.

If your periods are irregular, this calculator won't be accurate. Irregular periods can be a sign of PCOS or other problems that are usually treatable. When to see a doctor →

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