Google Slides: The ULTIMATE guide
JANUARY 7, 2019
Changing slide size: Google Slides defaults to the standard widescreen 16:9 aspect ratio. The standard 16:9 aspect ratio is widely used because it fits perfectly on most widescreen screens and projectors. If you want to resize your object without it being warped or stretched, check the Lock aspect ratios box. Images typically need to be under 2MB and in JPEG, GIF or PNG format to upload correctly. To the right of the window you will see a button with a pen icon.