Pregnancy Calculator
Find your estimated conception date, due date, and current pregnancy week using our accurate conception calculator. Get a personalized pregnancy timeline based on your last menstrual period and average cycle length—trusted by thousands of expectant parents.
Calculate Your Pregnancy Details
How Our Pregnancy Calculator Works
Understand the science behind pregnancy dating and conception estimates.
Enter Your LMP Date
Input the first day of your last menstrual period (LMP), which serves as the baseline for most due date calculations.
Select Cycle Length
Enter your average menstrual cycle length for accuracy. The default is 28 days, but you can adjust for shorter or longer cycles.
Get Instant Results
See your estimated conception date, due date, current week, and trimester instantly.
Medical Calculation Method
Our conception date calculator uses Naegele’s Rule—the standard method used in obstetrics. It adds 280 days (40 weeks) to the first day of your last menstrual period, adjusted for your average cycle length. Formula: Due Date = LMP + 280 days - (Cycle Length - 28 days) This approach provides an estimated due date (EDD) that aligns with medical practice and EDD calculators used by healthcare providers.
Formula: Due Date = LMP + 280 days - (Cycle Length - 28 days)
This approach provides an estimated due date (EDD) that aligns with medical practice and EDD calculators used by healthcare providers.
Additional Pregnancy Tools
Age Calculator
Find your exact age in years, months, and weeks.
Height Calculator
Compare height in inches, feet, and centimeters.
BMI Calculator
Check your Body Mass Index for healthy weight ranges.
Body Fat Calculator
Estimate your body fat percentage for prenatal fitness awareness.
BMR Calculator
Find your Basal Metabolic Rate for balanced nutrition.
TDEE Calculator
See your Total Daily Energy Expenditure to support a healthy pregnancy.
Understanding Pregnancy Calculations
Pregnancy is measured in gestational weeks starting from your last menstrual period. The conception date typically occurs about two weeks after that, during ovulation.
Key Pregnancy Terms
Gestational Age
The age of your pregnancy measured from the first day of your last menstrual period (LMP).
Estimated Due Date (EDD)
The predicted date of delivery, usually 40 weeks from LMP.
Trimesters
Pregnancy is divided into three stages: first (1–12 weeks), second (13–27), and third (28–40).
Important Considerations
Accuracy Limitations
Only 5% of babies arrive on their exact due date; most come within two weeks before or after.
Irregular Cycles
Women with unpredictable cycles may need ultrasound confirmation for accuracy.
Medical Consultation
Always confirm your EDD and gestational age with your doctor.
First Trimester Dating
Scans between 6–12 weeks provide the most reliable pregnancy dating.
Why Use a Pregnancy Timeline Calculator
Knowing your due date helps track pregnancy progress and plan for key milestones. This pregnancy timeline calculator also identifies trimester transitions, estimated conception date, and major prenatal checkup points.
If your cycles are irregular or you conceived through IVF, you can use this tool along with an IVF transfer due date or early ultrasound for greater precision.
Frequently Asked Questions
Common questions about pregnancy calculations and due dates
Your due date is estimated by adding 280 days (40 weeks) to the first day of your last menstrual period.
Yes. Your conception date is typically about two weeks after your last menstrual period, depending on your cycle.
You can adjust the cycle length field to match your average. The calculator automatically recalculates your due date.
Use the IVF transfer due date option to get a more precise EDD, based on embryo transfer timing.
Gestational age counts weeks from your last period, not from conception.
Yes. The pregnancy timeline calculator shows your current week and key developmental milestones.
No. Only about 5% of births occur exactly on the predicted date; it’s an estimate.
Pregnancy is split into three trimesters—early (1–12 weeks), middle (13–27), and final (28–40 weeks).
You can, but ultrasound dating offers higher accuracy for irregular cycles.
Schedule an appointment around 6–8 weeks for an early scan and official dating confirmation.