The default font style in a spreadsheet is Roboto. To change the font style of text in a cell:
Select the cell/cell range you want to change the font style for.
Click on the font style drop-down menu in the Toolbar.
Select your desired font style from the available options.
Go to the font style drop-down menu in the Toolbar.
Click Add More Fonts.
Click the + symbol next to a font to add it to My Fonts. The Font Library provides 500+ font styles to choose from.
To remove fonts from My Fonts, you can simply click the - symbol next to the font style.

| Old | New |
Arial | Roboto (default) |
Arial Black | Archivo Black |
Book Antiqua | PT Serif |
Calibri | Lato |
Comic Sans MS | Patrick Hand |
Courier New | Roboto Slab |
Garamond | PT Serif |
Georgia | Droid Serif |
Lucida Console | Droid Serif |
Tahoma (default) | Lato |
Times New Roman | Droid Serif |
Trebuchet MS | Ubuntu |
Verdana | Open Sans |