Clinical calculator
Pregnancy due date (EDD)
Estimated due date and gestational age from the last menstrual period, adjusted for cycle length.
Inputs
Naegele's rule, adjusted when your cycle is not 28 days.
Estimated due date
-
Gestational age today-
Trimester-
For reference only. An estimated due date is a prediction, not a diagnosis. Dating
should be confirmed clinically, usually by ultrasound. This tool is not a substitute for
professional judgement, and OlivHealth is not liable for any decision made using it.
Frequently asked questions
How is the due date calculated?
By Naegele’s rule: last menstrual period (LMP) + 280 days (40 weeks). The tool also shows current gestational age.
How accurate is an LMP-based due date?
It assumes a regular 28-day cycle. An ultrasound dating scan is more accurate, especially with irregular cycles.
Run your whole hospital, not just this tool.
This is a free, standalone tool. Inside OlivHealth the same thing happens automatically across your whole hospital, records, billing, queue and analytics in one place.