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Pregnancy Due Date Calculator

Find your due date from your last period, conception date or IVF transfer — plus how many weeks pregnant you are and when each antenatal test is due.

Your details

Calculate fromFirst day of last periodUsual cycle lengthdays28 if you're not sure

Pick a date to see your due date.

How it's calculated

From your last period: Naegele's rule — first day of last period + 280 days, adjusted by the difference between your cycle length and 28 days.
From conception: conception date + 266 days. IVF: day-5 transfer + 261 days, day-3 transfer + 263 days.
Weeks pregnant are counted from the due date, so every method gives the same answer for the same pregnancy.
Scan and test windows follow the standard antenatal schedule used in India (MoHFW / WHO).

Sources

Questions people ask

How accurate is a due date calculator?

It gives the standard estimate doctors start from. Only about 4% of babies are born on their due date — most arrive between 37 and 42 weeks. A first-trimester ultrasound is the most accurate way to date a pregnancy.

My cycle isn't 28 days. Does that matter?

Yes. Enter your usual cycle length and the calculator shifts the due date: a 32-day cycle moves it 4 days later.

How do I calculate my due date after IVF?

Choose IVF and the transfer day. A day-5 (blastocyst) transfer adds 261 days to the transfer date; a day-3 transfer adds 263 days.

When is the NT scan done?

Between 11 weeks 0 days and 13 weeks 6 days. The calculator shows your exact dates.

This website provides general educational information and is not a substitute for professional medical diagnosis, treatment or emergency care. Always consult a qualified healthcare professional.