Estimate due date from LMP or conception date.
Quick planning, rough comparisons, and checking whether your assumptions are in the right range before you rely on final quotes or advice.
Review the assumptions below, then compare with related calculators if your decision depends on rates, eligibility, or provider-specific rules.
How this calculator works
- LMP adds 280 days.
- Conception date adds 266 days.
- The result is an estimate, not a guarantee.
Worked example
An LMP-based estimate uses 40 weeks from the first day of the last period.
Important assumptions
- Cycle irregularity can shift the estimate.
- Ultrasound dating may differ from this result.
- Use clinical guidance for medical decisions.
FAQ
Are these calculators free?
Yes. lankacalculator tools are free to use and designed to be quick to access without sign-up.
How accurate are the results?
The calculators use clear assumptions and formulas, but results are estimates and should be checked against official documents or provider terms.
Can I use this on mobile?
Yes. The layout is built to work cleanly on phones, tablets, and desktops.
Do you store my inputs?
No account is required for these tools, and calculator inputs are not stored as user profiles in this v1 setup.