Estimate your baby's due date from your last period, conception date, IVF transfer, or ultrasound — and see your current gestational week and trimester.
Enter a date to see your estimate.
How to use this calculator
Select your calculation method from the dropdown, then enter the relevant date. If you're using IVF, also choose whether your embryo was transferred on day 3 or day 5. The calculator instantly shows your estimated due date, current gestational week, trimester, and how many days remain until your due date.
Understanding your result
Your estimated due date (EDD) is a statistical midpoint — about 50% of pregnancies deliver within a week either side of it. The gestational week tells you how far along you are, measured from the equivalent of your last period. A trimester breakdown helps you track key milestones: Trimester 1 covers weeks 1–13, Trimester 2 covers weeks 14–27, and Trimester 3 covers weeks 28 through birth.
Disclaimer
Menstrual cycles, fertility, and pregnancy vary significantly between individuals. Results from this tool are statistical estimates and may not reflect your personal health. This is not medical advice, a diagnosis, or a substitute for professional care. If you have concerns about your pregnancy or reproductive health, consult a gynaecologist or healthcare provider.
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Frequently asked questions
How is a due date calculated?
The most common method uses the first day of your last menstrual period (LMP): due date = LMP + 280 days (40 weeks). Other methods include conception date (+266 days), IVF day-5 transfer (+261 days), IVF day-3 transfer (+263 days), and an ultrasound-confirmed EDD which takes precedence over all other methods.
Why do different methods give different dates?
Each method uses a different starting point. LMP assumes ovulation at day 14 of a 28-day cycle. Conception dating is more direct but requires knowing the exact date. IVF dates are highly precise because the transfer day is known. Ultrasound EDD, especially in the first trimester, is considered the most accurate when available.
Is this medical advice?
No. This calculator provides estimates for informational purposes only. Always consult a qualified healthcare professional before making decisions about your health.
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