Estimate pregnancy dating from an LMP, conception date, IVF transfer, or existing estimated due date.
Calculate with the Pregnancy Due Date Calculator
Enter the details below. Your values stay in this browser and are validated before results are shown.
Pregnancy Due Date Calculator results
How to use the Pregnancy Due Date Calculator
- Select the requested method and unit system where available.
- Enter measured values carefully using the labels and active units.
- Select Calculate or press Enter.
- Read the estimate together with its method, assumptions, limitations, and safety notice.
Worked example
An LMP date plus 280 days gives the conventional 40-week estimate for a 28-day cycle.
Interpreting the estimate
The displayed date is an estimate. Early ultrasound and clinical assessment may establish or revise the best obstetric estimate.
Limitations
- Cycle irregularity, fertility treatment details, ultrasound dating, and individual variation can affect results.
- The calculator cannot assess pregnancy viability or health.
Frequently asked questions
Can an ultrasound change the estimated due date?
Clinical assessment and early ultrasound may establish or revise pregnancy dating. Follow the estimate recorded by the treating maternity-care team.
Is the pregnancy due-date calculator a medical assessment?
No. It provides an educational estimate from the values entered and cannot account for every individual or clinical factor.
Does CalculatorCheck store my health information?
No. The calculation runs in your browser, and the entered values are not sent to a server or added to the page URL.