Adding alternative text to photos and images that you’ve inserted in OneNote for Windows 10 is a useful way to provide descriptions of visual content in your notes. These descriptions can provide important context to people with visual or cognitive impairments.
To add alt text to an image, do the following:
On any page in OneNote, right-click an image you have inserted.
On the menu that appears, click Picture, and then click Alt Text.
In the Alt Text dialog box, type a descriptive Title for the selected image. You can also add a more detailed Description of the image.
Click Done to save your changes.
Note: To change or remove existing alt text, edit or remove the existing information in the Title and Description boxes.