Find the number of days between a start and end date by subtracting.
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=B2-A2Excel stores dates as serial numbers, so subtracting one date from another gives the day count. Format the result cell as Number (not Date) to see the count.
=DATE(2026,1,31)-DATE(2026,1,1)→3030 days between Jan 1 and Jan 31.
Whole months / years
=DATEDIF(A2, B2, "m")Use "m" for months or "y" for years.
Excel inherited the date format. Change the cell's number format to General or Number.
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