Days, weeks, months and weekdays between two dates — counted the way people mean.
358 days — 11 months and 24 days
Counting forward from today, the two dates are 358 calendar days apart. The month figure counts whole calendar months and then the days left over, which is what people mean by "three months and four days" — dividing days by 30 gives a different and less useful answer, because months are not a fixed length. The weekday count excludes Saturdays and Sundays only; public holidays vary by country and are not applied.
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