Pregnancy Calculator

Estimate current pregnancy week, trimester, and timeline milestones from a due date or the first day of the last period.

Preparing Pregnancy Calculator

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Input

Choose whether you are starting from the last menstrual period or from an estimated due date, then enter the matching date to map the pregnancy timeline. This tool shows the result instantly without step-by-step output.

Input summary

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How to use Pregnancy Calculator

Start from the pregnancy date you already know, and the calculator will estimate where the pregnancy falls in weeks and trimesters today.

What this calculator is for

This calculator is for pregnancy timeline tracking and planning conversations. It helps translate one known date into gestational week and trimester context, but formal pregnancy dating is best confirmed in prenatal care.

Tips

Use the first day of the last menstrual period, not the last day, when choosing the LMP mode.
If an ultrasound-based due date has been set in care, that date usually deserves priority over a rough memory-based estimate.
Cycle irregularity can shift date-based estimates, so treat this as a guide rather than a final dating decision.