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Due Date Calculator

Estimate your baby’s due date from your last period, conception date or IVF transfer date and see the full week-by-week calendar.

days

Days from the first day of one period to the first day of the next.

Estimated due date

Tue, Jul 8, 2025

Estimated conception
Tue, Oct 15, 2024
Pregnancy start (week 1, day 1)
Tue, Oct 1, 2024
First trimester ends
Mon, Jan 6, 2025
Second trimester ends
Mon, Apr 14, 2025
Full term (39 weeks)
Tue, Jul 1, 2025
Common birth window (37–42 weeks)
Jun 17 – Jul 21, 2025

This result is not medical advice.

Pregnancy calendar

WeekDatesTrimesterMilestone
Week 1Oct 1 – Oct 7, 2024First
Week 2Oct 8 – Oct 14, 2024First
Week 3Oct 15 – Oct 21, 2024First
Week 4Oct 22 – Oct 28, 2024FirstPeriod is due; a home test can usually detect pregnancy
Week 5Oct 29 – Nov 4, 2024First
Week 6Nov 5 – Nov 11, 2024FirstHeartbeat is often visible on ultrasound
Week 7Nov 12 – Nov 18, 2024First
Week 8Nov 19 – Nov 25, 2024FirstEarly prenatal visit and dating scan are common
Week 9Nov 26 – Dec 2, 2024First
Week 10Dec 3 – Dec 9, 2024First
Week 11Dec 10 – Dec 16, 2024First
Week 12Dec 17 – Dec 23, 2024FirstFirst-trimester screening window (weeks 11–14)
Week 13Dec 24 – Dec 30, 2024First
Week 14Dec 31 – Jan 6, 2025FirstSecond trimester begins
Week 15Jan 7 – Jan 13, 2025Second
Week 16Jan 14 – Jan 20, 2025Second
Week 17Jan 21 – Jan 27, 2025Second
Week 18Jan 28 – Feb 3, 2025SecondDetailed anatomy scan window opens (weeks 18–22)
Week 19Feb 4 – Feb 10, 2025Second
Week 20Feb 11 – Feb 17, 2025SecondHalfway point
Week 21Feb 18 – Feb 24, 2025Second
Week 22Feb 25 – Mar 3, 2025Second
Week 23Mar 4 – Mar 10, 2025Second
Week 24Mar 11 – Mar 17, 2025SecondGlucose screening window opens (weeks 24–28)
Week 25Mar 18 – Mar 24, 2025Second
Week 26Mar 25 – Mar 31, 2025Second
Week 27Apr 1 – Apr 7, 2025Second
Week 28Apr 8 – Apr 14, 2025SecondThird trimester begins
Week 29Apr 15 – Apr 21, 2025Third
Week 30Apr 22 – Apr 28, 2025Third
Week 31Apr 29 – May 5, 2025Third
Week 32May 6 – May 12, 2025ThirdGrowth checks and birth-plan talks are common
Week 33May 13 – May 19, 2025Third
Week 34May 20 – May 26, 2025Third
Week 35May 27 – Jun 2, 2025Third
Week 36Jun 3 – Jun 9, 2025ThirdWeekly visits are common from here
Week 37Jun 10 – Jun 16, 2025ThirdEarly term begins
Week 38Jun 17 – Jun 23, 2025Third
Week 39Jun 24 – Jun 30, 2025ThirdFull term begins
Week 40Jul 1 – Jul 7, 2025ThirdEstimated due date week

About the due date calculator

Your estimated due date (EDD) is the day you complete 40 weeks of pregnancy. The classic way to find it is Naegele’s rule: add 280 days to the first day of your last period. If your cycle is longer or shorter than 28 days, the date is moved by the difference, because ovulation happens later or earlier.

If you know when you conceived, the due date is 266 days later. For IVF, the clock starts from the transfer date: the due date is 266 days after the transfer minus the age of the embryo, so 261 days for a 5-day blastocyst and 263 days for a 3-day embryo.

The results include the end of each trimester, the start of full term at 39 weeks and a calendar for all 40 weeks. Due dates are estimates; your care provider may adjust yours after an early ultrasound.

Formula

  • From last period: due = LMP + 280 days + (cycle length − 28) days
  • From conception: due = conception + 266 days
  • IVF: due = transfer date + 266 days − embryo age (3 or 5 days)

Example

A last period that began on May 31, 2023 gives a due date of March 6, 2024, 280 days later. The count crosses February 29, 2024, so leap years are handled correctly.