justyourcalculatorDue Date Calculator
Estimate your due date four ways, with the key dates of your pregnancy.
- 100% Free
- Instant Results
- No Sign Up
Due Date Calculator
Estimate your baby's due date
Usually 21 to 35 days.
More Fitness & Health Calculators
View all calculators- Pregnancy CalculatorHow far along you are, due date and timeline
- Pregnancy Conception CalculatorWhen you likely conceived
- Pregnancy Weight Gain CalculatorHealthy pregnancy weight gain by week (IOM)
- Conception CalculatorYour fertile window and best days to conceive
- BMI CalculatorBody mass index and healthy weight range
- Calorie CalculatorDaily calories to maintain, lose or gain weight
- Body Fat CalculatorBody fat % by the US Navy tape and BMI methods
- BMR CalculatorBasal metabolic rate by three formulas
- Macro CalculatorDaily protein, carbs and fat for your goal
- Calculators
- 204+
- Free to use
- 100%
- Results as you type
- Instant
How the due date calculator works
The standard due date is 280 days (40 weeks) after the first day of your last period, adjusted for cycle length (Naegele's rule). If you know the conception date, it's 266 days after conception.
For IVF, the due date is the transfer date plus 266 days minus the embryo's age: 263 days for a day 3 embryo and 261 days for a day 5 blastocyst. An early ultrasound can refine any of these.
Using and checking your result
Published by JustYourCalculator. Check the units and assumptions above, and compare a known example before relying on the output. Calculations use browser arithmetic and may round displayed values.
This tool provides an estimate, not a diagnosis, treatment plan or individualized medical advice. Population formulas may not fit children, pregnancy, athletes or people with health conditions. Discuss health decisions with a qualified clinician.
Share links may contain your input values. Anyone with the URL can read them; avoid sharing sensitive personal or financial information.