Due Date Calculator

days
Health Updated 14 Jun 2026

Due Date Calculator is a health and wellness calculator that helps you calculate date differences, days between dates, or future/past dates. The formula used is: EDD = LMP + 280 days (adjusted for cycle length)\nConception ≈ LMP + 14 days. Enter values using the units shown next to each input field (e.g. kg, cm, years).

Formula

EDD = LMP + 280 days (adjusted for cycle length) Conception ≈ LMP + 14 days
  • Due Date Calculator gives you a fast estimate using your inputs and updates instantly when you change any value.
  • Formula: EDD = LMP + 280 days (adjusted for cycle length)\nConception ≈ LMP + 14 days
  • Input definitions: • Average cycle length: the numeric average cycle length used in the calculation
  • Enter values using the units shown next to each input field (e.g. kg, cm, years).
  • This calculator uses widely accepted health formulas and returns screening estimates only. It does not replace a diagnosis from a qualified healthcare professional.
  • Compare your result with published reference ranges. Values outside the normal range warrant a conversation with your doctor.
  • Practical tip: test a low, medium, and high scenario to understand sensitivity before making decisions.

Example Calculation

Inputs
  • Average cycle length: 28 days

Suppose you enter: Average cycle length = 28. The calculator applies the formula (EDD = LMP + 280 days (adjusted for cycle length)\nConception ≈ LMP + 14 days) and shows all output values below. Change any input field to immediately see how the result changes.

Frequently asked questions

What is the Due Date?
The Due Date Calculator is a health and wellness calculator that helps you calculate date differences, days between dates, or future/past dates. Enter values using the units shown next to each input field (e.g. kg, cm, years).
When should I use this calculator?
Use this calculator whenever you need a quick, accurate result for date differences, days between dates, or future/past dates without working through the arithmetic manually.
What units should I enter?
Enter values using the units shown next to each input field (e.g. kg, cm, years).
How accurate are the results?
This calculator uses widely accepted health formulas and returns screening estimates only. It does not replace a diagnosis from a qualified healthcare professional.
How do I interpret the result?
Compare your result with published reference ranges. Values outside the normal range warrant a conversation with your doctor.
How can I verify the calculation manually?
Use the displayed formula and work through the numbers step by step. If your manual result differs slightly, check rounding and unit conversions first.
Can I use this for planning and budgeting?
Yes. Run best-case, expected, and worst-case inputs to compare outcomes and make safer planning decisions.

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