Conception Date Calculator
Health & FitnessEstimate the day conception most likely occurred, based on your menstrual cycle length.
Estimated Conception Day (day of cycle)
The day of your cycle, counting the first day of your last period as day 1, when conception most likely occurred.
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Creators
Odeh Ahwal0people find this calculator helpful
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Helpful
Saved
Embeds
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Frequently Asked Questions
How is conception date estimated?
Conception typically happens around ovulation, which is estimated to occur 14 days before your next period. Counting from the first day of your last period, this puts the likely conception day at your cycle length minus 13.
How accurate is this estimate?
Because the exact timing of intercourse relative to ovulation varies, the true conception date can fall within about a week of this estimate.
Is this the same as my due date calculation?
Conception date and due date are related but calculated differently. Your due date is typically about 266 days after conception, or 280 days after the first day of your last period.
Does this work for irregular cycles?
This calculator assumes a fairly regular cycle. If your cycles vary significantly in length, the estimate becomes less reliable.
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