How to Add Drop Down List in Google Sheets
Learn how to add, copy, and remove a dropdown list in Google Sheets. Learn how you can apply basic formatting to dropdown Google Sheets such as alphabetizing and color coding. Also restrict input to the listed options in the dropdown list.
How to Add Dropdown List from a range of Cells
Step 1: Select the target cells
Select the cells where you want to add a dropdown list.

Step 2: Select Data validation from the Data menu on the toolbar.
Click Data from the main toolbar, then select Data validation from the list.

Step 3: Set to load the list of items from a range
On the right of the Criteria label is a drop-down box where we can select where to get the list of items for the drop-down box. By default, List from a range is selected, which is the option we need.

Click the Range icon on the textbox beside it.

Step 4: Select the range with the options for your dropdown menu, then click OK.

Click Save.

You have now inserted dropdown lists to the selected cells!


How to add dropdown in Google Sheets by manually inputting options
You can add Dropdown in google sheets without having to store the menu options anywhere in your spreadsheet. You can instead add the dropdown options manually. Here are the steps:
Step 1: Select the target cells
Select the cells where you want to add a dropdown list.

Step 2: Select Data validation from the Data tab on the main toolbar.
Click Data from the main toolbar, then select Data validation from the list.


Step 3: In the criteria dropdown box, select the List of items option.
On the right of the Criteria label is a drop-down box where we can select where to get the list of items for the drop-down box. Click it and select List of items.

Step 4: Manually input your dropdown menu options.
Start typing the items in the textbox beside it. Separate each item with a comma.
Step 5: Click Save.
After adding all of your options, click Save.

You have now inserted dropdown lists to the selected cells!


How to Copy Google Sheets Dropdown Menu
To copy the dropdown from one cell to another, simply copy the cell containing it and then paste it to the target cell.

If you want to extend the dropdown menu down the same column, you can click the last cell with the dropdown menu, click its lower-right corner square, and then drag it down the column.

How to Remove Google Sheets Dropdown Menu
Simply pressing Delete on your keyboard will remove the selected option on the cell but will not remove the dropdown menu. Here are the steps to remove a dropdown menu from a range of cells:
Step 1: Select the cells
Select the cells where you want to remove the dropdown menu.

Step 2: Open Data validation from the Data tab of the main toolbar.
Click Data on the main menu, then select Data validation from the drop-down menu.

Step 3: Click Remove validation.

You can check the screencap below to see how it works:

FAQs
What if I try to input an option that is not on the dropdown menu?
If you attempt to input data that is not in the dropdown list, you will get a warning:

You can set the cell to reject invalid input by doing the following steps:
Step 1: Select the cells
Step 2: Open data validation from the Data tab on the main toolbar.
Step 3: Check Reject input

You will get this message when you input a value not listed in the dropdown box:

How to alphabetize the drop down list?
If you input the list manually in the Data validation box, you can only manually arrange the items in the box. If the list is in a sheet, you can sort Google sheets dropdown using one of the methods in this tutorial.
How to color code a dropdown List?
You can color code a dropdown list by using conditional formatting. Click here to color code lists in Google Sheets.