Ovulation & period calculator

Cycle length is from the first day of one period to the first day of the next. 21–35 days is common.

Next 6 cycles

Ovulation is estimated at 14 days before the next period. It varies from cycle to cycle, especially with irregular cycles or PCOS, so don't rely on this for contraception. Ovulation kits or your gynaecologist can confirm it.

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