Pregnancy Week Calculator

Pregnancy weeks are counted from the first day of the last menstrual period (LMP). Day 0 of week 0 is the first day of LMP, and since ovulation and conception typically occur about 2 weeks later, there is approximately a 2-week difference between actual and calendar pregnancy duration. This tool calculates the exact pregnancy week in 'weeks + days' format by entering the LMP and any reference date (defaulting to today).

Pregnancy is divided into three trimesters: first (up to 13 weeks, organogenesis), second (14-27 weeks, stable period), and third (28+ weeks, growth phase), each with specific checkup schedules and precautions. The due date is calculated using Naegele's rule (LMP + 280 days), and the estimated conception date (LMP + 14 days) is also displayed. The progress bar provides a visual overview of where you are in the pregnancy journey, useful for prenatal care planning.

If pregnancy duration exceeds 42 weeks (294 days), a warning is displayed recommending medical consultation. This indicates a duration significantly beyond the normal range and may warrant medical attention. This tool is for informational purposes and is not a medical diagnosis. Always follow your physician's guidance."