Free Pregnancy Due Date Calculator
Estimate your pregnancy due date and current gestational week using Naegele's rule from the first day of your last menstrual period.
days
Current Gestational Week
12 weeks
Extra Days0 days
Days Until Due Date196 days
Weeks Remaining28.0 weeks
Current Gestational Week vs Days Since Last Period Started
Naegele's Rule
The estimated due date is 280 days (40 weeks) from the first day of the last menstrual period (LMP).
Due Date = LMP + 280 days
Trimester Breakdown
Only about 5% of babies are born on their exact due date. Most arrive within 2 weeks of the estimate.
Example Calculation
A woman whose last period started 84 days ago.
- 01Gestational week = floor(84 / 7) = 12 weeks
- 02Extra days = 84 - 12 x 7 = 0
- 03Days remaining = 280 - 84 = 196 days
- 04Weeks remaining = 196 / 7 = 28.0 weeks
Frequently Asked Questions
Learn More
Understanding BMI: What It Means and How to Calculate It
Learn what BMI is, how to calculate it, what the ranges mean, and the limitations of body mass index as a health metric. Comprehensive guide with formulas and context.