Excel library

Excel Date and Time Formulas

Excel stores dates as numbers (days since 1 January 1900) and times as fractions of a day. Once that clicks, most date problems become simple arithmetic: subtract two dates for days between them, add 7 for next week, multiply a time by 24 for hours.

Functions such as DATEDIF, EDATE, EOMONTH, WORKDAY and NETWORKDAYS handle the awkward cases: whole months and years, month ends, and skipping weekends and holidays.

These tutorials cover date differences, ages and service length, adding days, months and years, quarters and week numbers, converting text to dates, and calculating hours worked.

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