Smart Calculator

Conception Calculator

Conception Calculator

Calculate your most fertile days, conception dates, and estimated due dates. Plan your pregnancy with accurate fertility predictions and conception timing.

Conception Calculation
Enter your menstrual cycle details to calculate conception dates

Average menstrual cycle length ranges from 22 to 44 days (28 days is typical)

Understanding Conception

Conception Probability

  • Sperm can survive up to 5-7 days before ovulation
  • The last 3 days of fertile window have ~30% chance of conception
  • Conception is most probable on ovulation day
  • Any intercourse during fertile window may result in pregnancy

Calculation Method

  • Ovulation: LMP + (Cycle Length - 14 days)
  • Fertile Window: [Ovulation - 5 days, Ovulation]
  • Peak Fertile: [Ovulation - 2 days, Ovulation]
  • Due Date: Conception Date + 266 days

Timing for Conception

  • Best timing: 1-2 days before ovulation
  • Good timing: Day of ovulation
  • Moderate timing: 3-5 days before ovulation
  • Low probability: After ovulation day

Important Notes

  • This calculator provides estimates based on average cycles
  • Actual conception timing can vary by individual
  • Due dates are estimates using Naegele's Rule
  • Consult healthcare providers for personalized advice