Expert Guide: Calculate Days, Weeks, Months, and Years Between Dates in Excel

Calculating dates mentally can be a nightmare. Uneven month lengths, leap years, and seven-day weeks make it tough for even the sharpest minds.

Try this: How many days between January 9, 2015, and June 12, 2017? If it takes you more than a few seconds, you're normal. Let Excel handle it with precision.

Calculate Days, Weeks, Months, or Years Between Two Dates

Enter your start and end dates in separate cells, say D2 and E2.

Select the cell for the result and use these proven formulas (adjust cell references as needed):

• Days: =DATEDIF(D2, E2, "d")
• Weeks: =DATEDIF(D2, E2, "d") / 7
• Months: =DATEDIF(D2, E2, "m")
• Years: =DATEDIF(D2, E2, "y")

Note: Except for weeks, these count only complete periods, excluding partial ones.

Calculate Full Years, Months, and Days Between Dates

For a complete breakdown like "X years, Y months, Z days," combine formulas:

• =DATEDIF(D2, E2, "y") & " years, " &
  DATEDIF(D2, E2, "ym") & " months, " &
  DATEDIF(D2, E2, "md") & " days"

Note: Use Alt + Enter for line breaks and Ctrl + Shift + U to expand the formula bar.

As a seasoned Excel power user, I've relied on these DATEDIF tricks for years in project timelines and financial modeling. What's your go-to Excel formula for dates? Share in the comments! For more, check out 3 Crazy Excel Formulas That Do Amazing Things.