You can use the following basic formulas to add and subtract weeks from a date in Google Sheets:
Formula 1: Add Weeks to Date
=A1+7*(3)
This particular formula adds 3 weeks to the date in cell A1.
Formula 2: Subtract Weeks from Date
=A1-7*(1)
This particular formula subtracts 1 week from the date in cell A1.
The following examples show how to use each formula in practice with the following dataset in Google Sheets:
Example 1: Add Weeks to Date in Google Sheets
We can type the following formula into cell C2 to add 3 weeks to the date in cell A2:
=A2+7*(3)
We can then drag and fill this formula down to each remaining cell in column C:
Column C now displays the date in column A with exactly 3 weeks added to it.
Feel free to change the 3 in the formula to any value you’d like to add a different number of weeks to the original date.
Example 2: Subtract Weeks from Date in Google Sheets
We can type the following formula into cell C2 to subtract 1 week from the date in cell A2:
=A2-7*(1)
We can then drag and fill this formula down to each remaining cell in column C:
Column C now displays the date in column A with 1 week subtracted from it.
Feel free to change the 1 in the formula to any value you’d like to subtract a different number of weeks from the original date.
Additional Resources
The following tutorials explain how to perform other common tasks in Google Sheets:
How to Sum by Year in Google Sheets
How to Sum by Month in Google Sheets
How to Sort by Date in Google Sheets