health tools

Pregnancy Due Date Calculator

Estimate a pregnancy due date and conception timing from the first day of the last menstrual period.

Runs locally

Private by design

Enter your values

Local only

Dates are estimates and remain in this browser.

Estimated due dateJune 11, 2027
Estimated conceptionSeptember 18, 2026
Estimated first trimester endDecember 11, 2026

One idea, three depths

Choose how deeply to explain Pregnancy due date

Pregnancy due date: Estimate a pregnancy due date and conception timing from the first day of the last menstrual period.

Age 5Explain it to a 5-year-oldStart with a picture

Imagine using a measuring rule to make a rough estimate about a body, workout or calendar while remembering that people do not all behave like averages. Estimate a pregnancy due date and conception timing from the first day of the last menstrual period.

Age 15Explain it to a 15-year-oldConnect it to the formula

Estimate a pregnancy due date and conception timing from the first day of the last menstrual period. The estimate starts 280 days from the last menstrual period and adjusts for cycle length. Ultrasound dating and clinical assessment may establish a different date. Change one input or choice at a time and compare the result to see which part of the rule it controls.

CollegeExplain it at college levelState the model precisely

The browser applies a published screening, energy, exercise or calendar-estimation formula to the supplied values. The result is educational and cannot diagnose, prescribe or replace individualized clinical guidance. The estimate starts 280 days from the last menstrual period and adjusts for cycle length. Ultrasound dating and clinical assessment may establish a different date. Entries remain in this browser. The output is an educational estimate, not medical advice, diagnosis or a treatment recommendation. Discuss health, pregnancy, nutrition and exercise decisions with an appropriately qualified professional.

How this tool works

The estimate starts 280 days from the last menstrual period and adjusts for cycle length. Ultrasound dating and clinical assessment may establish a different date.

Privacy and limitations

Your entries and results stay in this browser. This calculator provides an educational estimate only and cannot diagnose a condition, prescribe intake or exercise, establish pregnancy dates, or replace advice from a qualified health professional.

Authoritative context

Review the CDC adult BMI guidance, American Heart Association target-heart-rate guidance, and ACOG pregnancy-dating guidancewhen those subjects apply.

Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS

These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.

APA 7

MW SysArc. (2026, July 21). Pregnancy Due Date Calculator. MW SysArc Tools. https://health.mwsysarc.com/pregnancy-due-date-calculator

MLA 9

MW SysArc. “Pregnancy Due Date Calculator.” MW SysArc Tools, 21 July 2026, https://health.mwsysarc.com/pregnancy-due-date-calculator. Accessed 4 Sept. 2026.

Chicago 17

MW SysArc. “Pregnancy Due Date Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed September 4, 2026. https://health.mwsysarc.com/pregnancy-due-date-calculator.

Harvard

MW SysArc (2026) ‘Pregnancy Due Date Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://health.mwsysarc.com/pregnancy-due-date-calculator (Accessed: 4 September 2026).

BibTeX and RIS records

BibTeX

@misc{mwsysarc_pregnancy_due_date_calculator_2026,
  author = {{MW SysArc}},
  title = {Pregnancy Due Date Calculator},
  howpublished = {MW SysArc Tools},
  year = {2026},
  url = {https://health.mwsysarc.com/pregnancy-due-date-calculator},
  note = {Published July 21, 2026; accessed September 4, 2026}
}

RIS

TY  - ELEC
AU  - MW SysArc
TI  - Pregnancy Due Date Calculator
T2  - MW SysArc Tools
PY  - 2026
DA  - 2026-07-21
Y2  - 2026-09-04
UR  - https://health.mwsysarc.com/pregnancy-due-date-calculator
N1  - Published July 21, 2026
ER  -

Clear answers

Frequently asked questions

What does the Pregnancy due date do?

Estimate a pregnancy due date and conception timing from the first day of the last menstrual period.

How does the Pregnancy due date work?

The estimate starts 280 days from the last menstrual period and adjusts for cycle length. Ultrasound dating and clinical assessment may establish a different date.

What can I learn from the Pregnancy due date?

It shows how the entered values or choices produce the result. Change one input at a time to compare outcomes and understand the underlying rule.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

This is an educational estimate, not medical advice, diagnosis or a treatment recommendation. Health, nutrition, pregnancy and exercise decisions should be discussed with an appropriately qualified professional.

Last reviewed . Calculations tested .

MW SysArc Certified