Pregnancy Due Date Calculator
Estimates your due date using Naegele's rule.
Result
- Estimated due date
- 6 Dec 2026
- End of first trimester
- 6 Jun 2026
How to use the pregnancy due date calculator
- Enter the first day of last period.
- The results update as you type, or press Calculate.
- Read the estimated due date first, then the supporting figures below it.
Formula
Due date = first day of last period + 280 days.
Worked example
For example, with these inputs:
- First day of last period: 1 Mar 2026
the calculator returns:
- Estimated due date: 6 Dec 2026
- End of first trimester: 6 Jun 2026
Background
Singapore's tropical climate means you lose more fluid through sweat, even when you are not exercising. Thirst, urine colour and how you feel are good guides, and needs rise during outdoor activity or heat waves.
Simple measurements such as weight, height and waist circumference are widely used to screen for health risks because they are cheap and easy to repeat. They are not diagnoses, but tracked over time they show whether lifestyle changes are working.
Frequently asked questions
How does the pregnancy due date calculator work?
It applies this formula: Due date = first day of last period + 280 days.
Is this a medical assessment?
No. These are general estimates. Speak to a doctor or polyclinic for advice about your health.