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Pregnancy Conception Calculator
About the Pregnancy Conception Calculator
Work backwards from your due date to estimate when conception happened.
How to use the Pregnancy Conception Calculator
- Enter your Known Due Date.
- Press Estimate Conception.
Formula and method
Conception is estimated at about 266 days (38 weeks) before the due date.
Tips
- Only around 5% of babies arrive on the exact due date.
Frequently Asked Questions
Sperm can survive for several days, and ovulation timing varies.