Our ovulation calculator helps to know your most fertile days. You need to just tell us the first day of your last menstrual period and average length of menstrual cycle.

When is the first day of your last period?

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What is the average length of your menstrual cycle? 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

Note: This tool helps you to calculate approximate fertile days assuming regular menstrual cycle. If you have irregular menstrual cycle, it may be difficult to calculate.