Is there a file size limit?

No practical limit for most operations.

Results are generated using standard algorithms for maximum accuracy.

free

Pregnancy Due Date Calculator — free

Calculate your pregnancy due date from last menstrual period.

First Day of Last Period

Average Cycle Length (days)

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Estimate ovulation date and fertile window.

Calculate the difference between two dates.

Calculate exact age from date of birth in years, months, days, hours, and minutes.