Presentation Slides

Core Concepts in Presentations

Regardless of which presentation software you are using, there are some accessibility testing techniques and concepts that apply broadly, which are outlined here. Specific details about how to check presentations for these concepts in a few common platforms are below. Reading this section first may be beneficial if you are a beginner to checking accessibility in presentations.

Reading Order

Reading order refers to the order that objects (text, images, etc.) are read by a screen reader.

  • In a presentation, reading order is often visually communicated. For example, text in separate text boxes may be in a visual order on the slide (left to right or top to bottom), but that may not be replicated in the reading order.
  • Specifying reading order in a presentation might be less intuitive than in another file, like a word document, because presentation software often does not contain headings functionality and each slide can contain multiple text boxes and other objects.
  • To manually test the reading order of a slide, use the tab button to navigate through the objects on the slide in the current reading order.
  • How to change the reading order of objects varies between presentation software.
    • A good place to start is finding how you can view the “order” of objects (meaning, which objects are visually furthest to the back or front, you may be familiar with this from placing some objects in front or behind others as you build a presentation). Changing that order will likely also change the reading order.
    • Please note that changing the object order can unintentionally place decorative objects in front of text, make sure to check for this.

Image Management

Images that convey information need alternative text to describe that information.

  • Alt text should explain why the image was included or provide the same information that the image is meant to convey, not just a description of the image with details that aren’t relevant or are already included in other text. For more information: Authoring Meaningful Alternative Text | Section508.gov
  • You may find the option to edit alt text in the context menu when an image is selected.
  • Images that do not convey information important to your presentation or are used for visual formatting do not need descriptive alt text.
    • If your software allows you to mark these images as decorative, do that.
    • If not, use a single space or “” as the alt text.

Transitions and Animations

Avoid using transitions or animations in your presentation. They can be distracting to some people, can be harmful for people with vestibular disorders, and blinking or flashing can cause seizures.

Use of Color

Color should not be used as the only way to communicate a piece of information.

Font Size and Style

  • There is no definitive minimum font size but many people recommend to use an 18-24 pt. minimum.
  • It is also recommended to:
    • use a sans-serif font where similar characters have some differentiation,
    • limit the number of fonts you use,
    • and avoid overusing all caps, italics, or bolded text.

Microsoft PowerPoint

Microsoft Accessibility Assistant

PowerPoint has a built-in accessibility assistant which can guide you through problems with a complete presentation or provide steps and documentation while building a presentation.

  • This guide will highlight common areas that need attention but you may also want to review Microsoft’s guide to Make your PowerPoint presentations accessible to people with disabilities and Accessibility Tools for Powerpoint.
  • To find the accessibility assistant navigate to Review then Check Accessibility. This opens an accessibility pane with an inspection of your document, which includes checking color and contrast, alt text, reading order, and slide titles.
  • Please note that the accessibility assistant is a helpful tool but using it alone won’t ensure your slides are accessible. For example, it may tell you that all images have alt text but you need to manually check to ensure that the alt text is meaningful and context relevant.

Reading Order

Each slide should have a descriptive title.

  • The slide title and reading order can be checked in the Screen Reader section under the Accessibility tab.
  • In the reading order pane, the text from the slide appears in the order the screen reader will read them. To change the order, use the up and down arrows or drag and drop the text.

Image Management

To edit alt text, navigate to the image’s context menu (or right click on the image) and select View Alt Text or select the Alt Text button in the accessibility tab.

  • The “Generate a description for me” function will attempt to describe the image but will not usually convey the same information you intend the image to communicate. Edit this description or write your own.
  • Some images may be purely decorative or used to visually emphasize something. These images don’t need alt text and should be marked as decorative.

Color Contrast

The built-in accessibility checker does not check for color contrast.

  • Use WebAIM Contrast Checker or AccessibleWEB Color Contrast Checker to compare foreground and background colors to ensure enough contrast exists between text and the background.
  • There is an option to inspect the presentation without color in the accessibility tab. Use this to ensure the presentation isn’t using color as the only way to communicate something, which makes your presentation accessible to people who are colorblind or have low vision.

Google Slides

Google Slides does not have its own internal accessibility checker, so the steps to check accessibility are the same as those listed in the Core Concepts in Presentations section of this guide with some additional information specific to Google.

Reading Order

In Google Slides, the object order control corresponds to the reading order.

  • The objects are read in order from the furthest back visually to the furthest in the front.
  • To change the order of an object, navigate to the context menu for the item (or right click on it), select Order, then bring the item forward or send it backward.

Image Management

  • To edit alt text, navigate to the image’s context menu (or right click on the image) and select Alt Text.
    • OR select Format Options from the toolbar and edit the image’s description.
  • Some images may be purely decorative or used to visually emphasize something. Google Slides doesn’t have the option to mark the image as decorative. In this case, use a single space or “” as the alt text.

Other Tools/Strategies

Grackle Slides can automatically check your presentation for accessibility, but your organization must use Google Workspace and allow add-ons.

Keynote (Apple)

Keynote does not have its own internal accessibility checker, so the steps to check accessibility are the same as those listed in the Core Concepts in Presentations section of this guide with some additional information specific to Keynote.

Image Management

  • To add alt-text in Keynote, select the image, select the Format button (icon of a paintbrush) in the toolbar, then select Image. Enter alt-text into the description box.
  • Some images may be purely decorative or used to visually emphasize something. Keynote doesn’t have the option to mark the image as decorative. In this case, use a single space or “” as the alt text.

Reading Order

  • In Keynote, the object order control corresponds to the reading order. The objects are read in order from the furthest back visually to the furthest in the front.
  • View the reading order by selecting View then Show Object List in the top menu bar. Drag and drop the objects in the object list to reorder them.

Navigating to Other Content Types

Use these links to continue (or return) to the other content types in this section: