Pregnancy Due Date Estimator
Calculate your estimated due date and current trimester based on the first day of your last period.
Pregnancy Due Date Estimator
Calculate your estimated due date and current trimester based on the first day of your last period.
This calculator is for informational purposes only and does not constitute medical advice. Consult a healthcare professional for personalised guidance.
How This is Calculated
Estimated due date is calculated using Naegele's rule: EDD = LMP + 280 days (40 weeks). Named after Franz Karl Naegele (1778–1851). Assumes a 28-day cycle with ovulation on day 14. Trimesters: 1st (weeks 1–12), 2nd (weeks 13–26), 3rd (weeks 27–40). Ultrasound dating in the 1st trimester is more accurate (±5–7 days).
Disclaimer: This tool provides estimates for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
