Pregnancy Due Date Calculator
Result
Ready
Pregnancy Due Date Calculator
Estimate due date based on last menstrual period.
What this calculator does
Pregnancy Due Date Calculator estimates outcomes from your inputs using deterministic browser-side formulas.
How it works
Converts date-time values to elapsed days using calendar-safe arithmetic.
- Enter your values in the input fields.
- Adjust options to match your scenario.
- The calculator applies the model to your inputs.
- Review the result and compare alternate scenarios.
Example calculation
Sample scenario:
- Start date: 2026-01-03
- End date: 2026-09-14
- Elapsed days: 254 days
FAQs
How should I use Pregnancy Due Date Calculator?
Run baseline inputs, then one alternate scenario.
Can I share this scenario?
Yes. Copy the share link URL.
Are results guaranteed?
No. Results are model-based estimates.
What should I verify?
Verify critical values against official records.
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Advanced details
Show advanced details
Formula
days = (end - start) / 86400Modeling assumptions
- Uses population-level equations and should not be interpreted as diagnosis.
- Hydration, medication, body composition, and clinical context can change real-world outcomes.
Planning guidance
Health outputs are informational only and are not medical diagnosis or treatment advice.