Health & Lifestyle
Pregnancy
Due Date Calculator
Estimate your arrival date. Use our simple tool to find out when you’re likely to meet your new family member based on your last period.
Due Date Tool
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Estimated Due Date
How Is the Due Date Calculated?
The standard method for calculating a pregnancy due date is Naegele’s rule. This formula assumes a regular 28-day menstrual cycle and pregnancy lasting 280 days (40 weeks) from the first day of your last menstrual period (LMP).
Adjusting for Cycle Length
Not everyone has a standard 28-day cycle. If your cycle is longer or shorter, our calculator adjusts the estimated due date accordingly. For every day your cycle is longer than 28 days, we add a day to the due date. Conversely, for every day it’s shorter, we subtract a day.
Note: This tool is for estimation only. Please consult with your healthcare provider for medical confirmation.