Pregnancy Conception Calculator
Calculate conception date, due date, and fertility window
Calculate Based On
Date Information
Cycle Information
days
days
Your Pregnancy Conception Results
Based on your provided information
January 1, 2024
Estimated Due Date: October 8, 2024
Week 12 of 40
Based on Due Date
Pregnancy Timeline
Fertility Window
Based on your cycle information, here is your estimated fertility window:
Most Fertile Days
January 10-15, 2024
This is when you're most likely to conceive
Ovulation Date
January 12, 2024
Estimated day of ovulation
About Conception Calculation
Conception typically occurs when a sperm fertilizes an egg, usually around the time of ovulation. Pregnancy is calculated from the first day of your last menstrual period (LMP), which is about 2 weeks before conception actually occurs.
Calculation Methods
| Method | Description | Calculation |
|---|---|---|
| Due Date | Calculate conception and LMP from due date | Conception = Due Date - 266 days |
| Last Menstrual Period | Based on first day of last period | Conception = LMP + 14 days |
| Conception Date | Based on actual conception date | Due Date = Conception + 266 days |
| Ultrasound Dating | Based on early ultrasound measurements | Most accurate method |
Cycle Information Reference
| Term | Description | Typical Duration |
|---|---|---|
| Cycle Length | Days from first day of period to day before next period | 21-35 days (avg 28) |
| Luteal Phase | Time between ovulation and next period | 10-16 days (avg 14) |
| Ovulation | Release of egg from ovary | ~14 days before next period |
| Fertile Window | Best time to conceive | 5 days before ovulation + ovulation day |
Understanding Your Cycle
- Cycle Length: Number of days from the first day of your period to the day before your next period starts
- Luteal Phase: Time between ovulation and the start of your next period (typically 12-16 days)
- Ovulation: Usually occurs about 14 days before your next period
- Fertile Window: 5 days before ovulation through the day of ovulation
Important Notes
- These calculations provide estimates - actual conception dates may vary
- Only about 5% of babies are born on their exact due date
- Sperm can live inside the female body for up to 5 days
- An egg is viable for about 12-24 hours after ovulation
- Always consult with your healthcare provider for accurate dating