Gestation Calculator – Determine Pregnancy Week, Trimester & Due Date
The Gestation Calculator helps you estimate the expected due date (EDD) of your baby based on your last menstrual period (LMP) or conception date. It’s a helpful tool for pregnant women, expecting couples, and healthcare providers to track the pregnancy timeline.
How to Use the Gestation Calculator
Choose one of the following methods:
- Enter the date of your Last Menstrual Period (LMP)
- Or, enter the known date of conception
The calculator will show your estimated due date, current gestational age, and trimester.
Gestation Date Formula
EDD (Estimated Due Date) = LMP + 280 days
(280 days = 40 weeks of pregnancy, counted from the first day of the LMP)
Example
LMP: January 1, 2025
→ Add 280 days → Due Date: October 8, 2025
Current Gestational Age: Automatically updated based on today's date.
Common Use Cases
- Tracking pregnancy week by week
- Preparing prenatal care schedule
- Estimating trimesters and milestones
- Birth planning and maternity leave calculation
- Medical consultations and ultrasound planning
Why Use a Gestation Calculator?
Knowing your due date helps ensure proper prenatal care and preparation. This tool offers a quick and accurate way to estimate gestation and pregnancy progress with minimal input.
Frequently Asked Questions (FAQs)
What if I don’t know my LMP?
You can use your conception date if known, or get an ultrasound for the most accurate dating.
Are all pregnancies exactly 280 days?
No, 280 days is an average. Full-term can range from 37 to 42 weeks.
Does this account for irregular cycles?
This calculator assumes a 28-day cycle. Adjustments should be made for longer or shorter cycles.
Is this accurate for IVF or assisted pregnancy?
For IVF, use the embryo transfer date or consult with your fertility provider.
Can I calculate trimester dates?
Yes, the tool shows your current trimester and estimated dates for each stage of pregnancy.
Related tools: Pregnancy Calculator, Ovulation Calculator, BMI Calculator.