Google docs add-on to set image size

SetImageSize is a Google Docs Addon that allows you to precisely set the size of an image. You can install it from this page. I had fun creating it and am curious if it will be used…


how to use

  • select an image in your document. The image should be in bmp, gif, jpg or png format. The text flow should also be set as ‘in-line’.
  • retrieve the size of the selected image with the “Get size” button.
  • change the width & height to your liking. You can set the size in pixels, inches & cm.
  • select “Apply” to set the new size.
  • use the padlock icon to lock and unlock aspect ratio.
  • the 1:1 button retrieves the original size of the image, i.e. before any changes.
  • you can edit your own preferred shortcuts.

privacy policy

This add on will only access the current document. It will not copy any document data anywhere outside of your document.


The add on works with bitmap images (bmp, gif, jpg, png) set to ‘inline’ only (because of Google Docs API limitation). When you select an image in Docs you can indicate how the text flows around the image. The options are ‘In line’, ‘Wrap text’ and ‘Break text’.


The programming took some getting used to. The scripts that manipulate the document object model actually run on the server and you need to use a call-back mechanism from the HTML in the browser (the sidebar) to the server-side script. Once that was clear the rest was pretty easy. I probably spent more time on the UI than on the server code. The reviewer gave quick and excellent feedback to make the add-on better. Pretty nice experience. Sometimes Google makes some breaking changes to the API (e.g. the security model), then it sometimes takes a bit of time for me to realise what is going on and find the time to fix it.



  1. Thank you for writing this plugin! It’s a big help for images with fine text. If the image isn’t at exactly the right size, the text becomes blurry. I’d love to just have a single button for “set to original size”.

  2. Thank you so much! I needed to resize some graphs for a bio paper and they all had to be the same size, which I couldn’t have done on google doc with out this add-on. Thank you!!!

  3. This is awesome. One thing that would be really helpful is being able to select all images or a set of images in a doc and doing a mass resize. Essentially having the ability to resize more than one image at a time.

  4. Hi! Nice idea! But I’m trying to install it to no avail! I’m able to select it but installation’s window claims that it is not able to find the site from where download the plugin. Please, any idea? Thanks!

  5. Hello Wouter,
    Every time I activate this add-on I get notified several weeks later by Google that there is a “security issue found on your account”. Google says that this add-on has too much of my private data and recommends I disable it, which I have done 3 times now. Out of the 14 add-ons I have installed right now, this is the only one producing this warning messages. Please make the necessary changes to prevent this from happening. Even if this function is very useful, I don’t want to give it access to sensitive documents. Thank you!

    1. thank you for the feedback. I am asking only for minimal access rights, only to the current document so I’m a bit stumped by that Google message. I have sent you an email to see if we can figure out what is going on…

  6. Thankyou so much, this has been one of the most annoying (missing) feature in google docs. You are an absolute legend!

  7. absolutely love this add-on! Has been a real time saver, but as pf this morning, I am no longer able to use it. Receiving error message: You do not have permission to call showSidebar.

    Please help.

  8. I just wanted to say thank you so much for updating your add-on! It’s working again for us. It’s been an invaluable tool, and we really appreciate you creating and maintaining it. Thanks again!!! Wishing you a very happy summer. : )

    1. thanks for the feedback, Google made some changes to the security model and it took a bit of time to figure out what was going on. I’m really glad the add-on is useful for you!

  9. This is a nice feature that is missing from the office Google Docs.
    Thank you for the add-on, and for the fixes due to the google api changes.

Leave a Reply

Your email address will not be published. Required fields are marked *