How to put a dropdown in Google Sheets

You can watch a video tutorial here.

To validate the data that is entered in Google Sheets, it is possible to define the list of values that are allowed by creating a drop-down list.  This is especially useful when creating data entry forms and you need to restrict the values that are entered. By restricting the values, you can ensure that the data collected is uniform and that less effort is spent on cleaning the data later.  You can either type out the list or refer to a list of allowed values.

Option 1 – Type the list of values

Step 1 – Open the Data Validation window

• Select the cell in which the drop-down list is to be created
• Go to Data > Data Validation

Step 2 – Enter the list of values

• Under Criteria select List of items
• Type the list of values  separated by a comma
• Ensure that the Show dropdown list in cell box is ticked
• Click Save

Step 3 – Check that the drop-down list has been added

• A drop-down arrow will appear on the right side of the cell 
• Expand the arrow to see the list of allowed values 

Option 2 – Refer to a list of values

Step 1 – Open the Data Validation window

• Select the cell in which the drop-down list is to be created
• Go to Data > Data Validation

Step 2 – Create a reference to the list of values

• Under Criteria select List from a range
• Click on the box to open the Select a data range box

Step 3 – Select the range

• Select the range of cells containing the values for the drop down
• Click OK

Step 4 – Set the other parameters

• Ensure that the Show dropdown list in cell box is ticked
• Click Save

Step 5 – Check that the drop-down list has been added

• A drop-down arrow will appear on the right side of the cell 
• Expand the arrow to see the list of allowed values