Question 1

How is pregnancy due date calculated?

Accepted Answer

Add 280 days (40 weeks) to first day of last menstrual period. Naegele's Rule: LMP + 1 year - 3 months + 7 days.

Question 2

How accurate is due date calculation?

Accepted Answer

Only about 5% of babies arrive on the due date. Most birth within 2 weeks before or after.

Question 3

How precise are these time calculations?

Accepted Answer

Our calculator handles time to millisecond precision. For most practical purposes, we use standard definitions (1 year = 365.25 days average).

Question 4

Do time zones affect these conversions?

Accepted Answer

Unit conversions (hours to minutes) are unaffected by time zones. For time zone conversions, use our dedicated time zone calculator.

Pregnancy Due Date Time Converter - Free Online

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