How to Calculate How Many Weeks You Are Pregnant
Calculating your pregnancy weeks is crucial for tracking your baby’s development and scheduling prenatal care. Our tool simplifies this process.
- Enter your date of birth (DOB) and last menstrual period (LMP) in the calculator above.
- Click ‘Calculate’.
- View your results and a visual representation below.
The formula we use is: Pregnancy Weeks = (Date Today – LMP) / 7. We subtract your LMP from the current date, then divide by 7 to get the number of weeks.
- Case 1: DOB: 01/01/1990, LMP: 08/15/2022. Result: 16 weeks, 3 days.
- Case 2: DOB: 07/15/1985, LMP: 11/20/2022. Result: 11 weeks, 2 days.
- Case 3: DOB: 12/31/1995, LMP: 05/10/2023. Result: 4 weeks, 6 days.
| Method | DOB | LMP | Result (Weeks) |
|---|---|---|---|
| Our Calculator | 01/01/1990 | 08/15/2022 | 16 |
| Naive Method (LMP + 280 days) | 01/01/1990 | 08/15/2022 | 16 |
| Pregnancy Weeks | Fetal Development |
|---|---|
| 8 | Baby’s tail is gone, and buds for future arms and legs appear. |
| 16 | Baby’s eyes can sense light, and the ears are close to their final position. |
- Always consult your healthcare provider for personalized advice.
- Consider using Naive Method (LMP + 280 days) as a backup if our calculator is unavailable.
- Track your pregnancy using apps or journals for a more detailed record.
- Regular prenatal check-ups are crucial for monitoring your health and your baby’s development.
What if my LMP is not regular?
Use the date of the first day of your most recent menstrual period. If your cycles are very irregular, consider using Naive Method as a backup.
Can I use this calculator if I’m trying to conceive?
No, this calculator is designed for women who are already pregnant. To estimate your due date before conception, use a due date calculator.
For more information, see: