The add on works with bitmap images (bmp, gif, jpg, png) set to ‘inline’ only (because of Google Docs API limitation).

you can edit your own preferred shortcuts.

the 1:1 button retrieves the size of the original image (as stored in the image).use the padlock icon to lock and unlock aspect ratio.You can set the size in pixels, inches & cm. change the width & height to your liking.retrieve the size of the selected image with the “Get size” button in the sidebar on the right.The text flow of the image has to be set to ‘in-line’. The image should be in bmp, gif, jpg or png format. select an image in your document by clicking on the image.You should now see the sidebar on the right. Then select “SetImageSize”, then select “show sidebar”. You do this by selecting “Add-ons” on the top menu. This feature has recently been added so maybe you want to try that first. Note: when I first created this Addon Google docs was not able to resize images. You can install it from this page. I had fun creating it and am curious if it will be used… SetImageSize is a Google Docs Addon that allows you to precisely set the size of an image.

Google docs resize image