justyourcalculatorConception Calculator
The best days to try for a baby, and the due date if you conceive.
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Conception Calculator
Your fertile window and best days to conceive
Usually 21 to 35 days.
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How the conception calculator works
Ovulation usually happens about 14 days before your next period, so in a 28-day cycle it's around day 14 and in a 32-day cycle around day 18. The fertile window is the 5 days before ovulation plus ovulation day, and the 3 days ending on ovulation are the most fertile.
The due date if you conceive is 266 days after ovulation. For irregular cycles these dates are less reliable.
Using and checking your result
Published by JustYourCalculator. Check the units and assumptions above, and compare a known example before relying on the output. Calculations use browser arithmetic and may round displayed values.
This tool provides an estimate, not a diagnosis, treatment plan or individualized medical advice. Population formulas may not fit children, pregnancy, athletes or people with health conditions. Discuss health decisions with a qualified clinician.
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