Lesson 39: Dates: DATE, YEAR, MONTH, DAY & WEEKDAY Exercises

Dates: DATE, YEAR, MONTH, DAY & WEEKDAY

Learn how Google Sheets stores dates, then practise DATE, YEAR, MONTH, DAY, WEEKDAY, DAYS and DATEVALUE: build dates, pull them apart, count days and fix dates stored as text.

Task 1 of 6

Build a real date from the year, month and day in columns A to C. Put it in D2.

Tip: while typing a formula, click a cell or drag across cells to insert references. Press Enter to check, and Tab to accept a function suggestion.

Dates are numbers in disguise

Google Sheets stores every date as a number: the count of days since December 30, 1899. January 1, 2026 is 46023. The date format just makes that number look like a date. This is why date math is simple: =B2-A2 is the number of days between two dates, and =A2+7 is a week later.

Function	What it does	Example
`DATE(year, month, day)`	Builds a date from its parts	`=DATE(2026, 3, 15)`
`YEAR`, `MONTH`, `DAY`	Pull one part out of a date	`=MONTH(A2)` → 3
`WEEKDAY(date, [type])`	Day of the week as a number	`=WEEKDAY(A2, 2)`: Monday = 1
`DAYS(end, start)`	Days between two dates	`=DAYS(B2, A2)`
`DATEVALUE(text)`	Turns date-looking text into a real date	`=DATEVALUE("2026-03-15")`

Watch out for

DATE rolls over: month 13 is January of the next year and day 0 is the last day of the previous month. That's handy for "same day next month" maths.
A result that shows as 46096 instead of a date just needs date formatting: Format › Number › Date.
Imported dates are often text (they sit on the left of the cell). Sorting and date math won't work on them until you convert them with DATEVALUE.