How it works
Formulas apply standard published equations or fee schedules in client-side JavaScript — not personalized medical or tax advice.
Formula
Due date ≈ LMP + 280 days (40 weeks) for standard Naegele’s rule estimate.
How to use Pregnancy Due Date Calculator
- Enter measurements or body stats in the units shown (toggle ft/in vs metric if available).
- Select presets such as activity level, fee tier, or coat count.
- Submit or live-update to refresh results.
- Write down outputs with a margin buffer for waste, taxes, or medical variance.
Worked examples
Concrete numbers and cases you can check against the tool above.
LMP April 10
Naegele estimate places due date around mid-January the following year — ultrasound may adjust by a week.
When to use Pregnancy Due Date Calculator
Early dating ultrasounds refine dates, but LMP math gives a starting point for prenatal scheduling.
Common use cases
- Plan maternity leave start windows.
- Schedule anatomy scan around recommended weeks.
- Compare LMP-based date vs IVF transfer date inputs.
Inputs and outputs
- Dates in local calendar
- LMP or conception inputs
Privacy
This tool runs entirely in your browser. Your data never leaves your device — nothing is uploaded to our servers.
Frequently asked questions
- Is this medical or tax advice?
- No. Due dates, TDEE, and paycheck outputs are estimates; consult clinicians, IRS guidance, or payroll for official figures.
- Do marketplace fees change?
- Platforms update fee tables; treat results as planning approximations and verify on seller dashboards.
- Should I add waste factor?
- Yes for concrete, tile, and mulch — many pros add 5–10% beyond raw calculator output.