A great little Chrome browser extension which allows you to add quick and easy highlights while presenting with Google Slides.

Once you have installed the extension, you can add highlights to Slides while you are presenting, as well as being able to download the highlighted slide as a PNG image file - in case you want to share it with your audience / class later!

It’s free, so you can grab the code or install the app from the Google Web Store.


All you need to do is install! No sign-in, no configuration - it just works. Once installed, you can use the following commands, which will get automatically added to the toolbar at the bottom of the presentation window.

Screenshot 1

Highlight gesture

Keyboard Shortcuts : H will enable the highlighter or cycle through the available colours, SHIFT-H will disable it.

Clicking the highlight tool button will activate the highlighter. You can cycle between three highlight colours by clicking on it again. To turn off the highlight tool, click through all the colours until the icon returns to a dull grey colour.

When the highlighter is active, you can use your mouse or touch device to draw straight highlight lines wherever you wish. You can build shapes using multiple lines. When you move between slides, the highlighter is automatically switched off, but your existing highlights are retained whilst you are still in presentation mode (meaning you can return to the highlighted slide).

Save save_alt

Keyboard Shortcut : SHIFT-S will trigger the save.

If you would like to save a copy of the highlighted slide, simply click the save command. This will download a PNG image of the slide to your device. You can then share it with your audience or class after the presentation is complete.

Clear delete_sweep

Keyboard Shortcut : SHIFT-C will trigger clear.

To clear all the highlights from the current slide, press clear. If the highlighter is active, it will remain so, but all existing lines will be removed.


The code is fully open-source but does contain code (many thanks!) from the projects below (any alterations or modifications are marked in the code). Everything else is copyright JD, 2019. This program is free software: you can redistribute it and modify it under the terms of the GNU General Public License (Version 3) as published by the Free Software Foundation. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Please see the full GNU General Public License for more details.

rough.jsGithub RepoCopyright © 2018 Preet ShihnMIT License
saveSvgAsPng.jsGithub RepoCopyright © 2014 Eric ShullMIT License
mousetrap.jsGithub RepoCopyright © 2012-2017 Craig CampbellApache 2.0 License

Recent Versions

The most recent versions of this extension are below, showing significant functionality changes and improvements.

  • 1.0.5Latest
    • Bug Fix

    • Fixed Google Fonts Issue

  • 1.0.4
    • Bug Fix

    • Changes to Fonts in Google Slides means that screenshots are now font-less :(

  • 1.0.1
    • Keyboard Shortcuts

    • Added Keyboard shortcuts to make control even easier!

  • 1.0.0Major Release
    • Initial Version

    • Initial version published online

      • Initial Code Commit (See here for details)

Need Help?

If you are a subscriber, then please email us directly or use the Get Help command under the About menu in any of our web apps to get help with this extension. Otherwise, please feel free to raise an issue on the code repository for this tool (you will need to sign up for a free Github account if you don't already have one). Only subscribers have full access to technical support, but we'll do our best to answer every query if we are able.

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