Pregnancy Due Date Calculator
Estimate your due date from your last period or your conception date — and see how far along you are today.
Your Dates
Not sure which date to use? “Last period” is the standard method most doctors start with.
Please enter a valid date that isn’t in the future.
Estimated due date
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Only about 1 in 20 babies arrive on their exact due date — this is a well-established estimate, not a guarantee. Your doctor may adjust this after an ultrasound.
How this is calculated
From last period: Most pregnancies last about 280 days (40 weeks) from the first day of your last period. If your cycle is longer or shorter than 28 days, the date shifts slightly to account for it.
From conception date: If you know roughly when conception happened, your due date is about 266 days (38 weeks) from that date.
Why it’s an estimate: Actual delivery dates vary naturally. A dating ultrasound in early pregnancy is the most accurate way to confirm timing — this calculator is a starting point, not a diagnosis.
Runs entirely in your browser — nothing you enter is stored, saved, or sent anywhere.