You know that websites need to be accessible to people with disabilities. But have you thought about your presentations?
Presentation accessibility means that your audience can experience, access, and understand your presentation. There are different considerations to presentation accessibility, depending on whether it is presented live or shared online. Knowing in advance how you want to present allows you to ensure that your content is fully accessible regardless of how the audience will experience it.
Accessibility considerations for live presentations
Fonts
There are two major font categories:
- Serif (fonts with finishing strokes on the ends of characters, such as Times New Roman)
- Sans Serif (font without finishing strokes, such as Calibri)
It’s generally agreed that sans-serif fonts are more readable and accessible at smaller point sizes than serif fonts. Serif fonts are often used for presentation elements that have a higher point size, such as headings and titles.
Several accessible fonts are common on today’s devices. Verdana and Tahoma are two fonts that are considered quite accessible and can be found across device platforms and formats.
For more detail about the accessibility of fonts, see WebAIM’s Fonts article.
Slide design and layout
It’s easy to create striking and well-designed presentations using the many available themes and templates. Using a theme’s built-in slide layouts promotes consistent and uniform design, which is essential for usability and accessibility. However, many themes use fonts that are either too small or too ornate to be truly accessible. Search online for accessible themes (there are plenty to choose from), or build an accessible theme using your agency logo, branding, colors, and conventions. Whichever option you choose, stick to the built-in formatting of the slide layouts with few or no modifications. Doing so will significantly increase the accessibility of the presentation with less additional work required later.
Layout guidelines
Make sure that the slide text is large enough to be seen by your audience. Refrain from trying to fit too much content on one slide, forcing the font point size to get too small. A good rule of thumb for slide content text is between 20–28 points, and for headers, aim for 36–44 points.
Here are some other things to consider when laying out presentations:
- Make sure each slide has a unique header. If there is more than one slide on the same topic, add a numerical identifier to the header, such as (1 of 2).
- Avoid using italics or all caps.
- Do not use color alone to indicate importance, but bold text is allowed.
- Make sure to display slide numbers.
- Keep transitions and animations simple. Fade or appear animations are acceptable, but avoid flashing and flying text.
Content guidelines
While slide design is important, your content also needs to be developed with accessibility in mind. Keep it brief, focusing on short blurbs or lists of information. It’s easy to overfill a slide with content, especially when font sizes are in the accessible range. When in doubt, break a dense slide into multiple slides to keep readability optimal.
Regarding readability, Plain Language Association International (PLAIN) identifies five general areas to consider when writing:
- Audience and purpose
- Structure
- Design
- Expression
- Evaluation
To learn more about each area, visit PLAIN’s “What is plain language?” webpage.
Color contrast is also important. Make sure the text color contrasts sufficiently with background colors. This applies to text in images as well. Contrast Checker is a helpful place to test different colors, and the results it provides conform to recognized accessibility standards.
Accessibility considerations for online/shared presentations
If you're posting your presentation on a website, sharing it on a slide service, or emailing it to users, there are additional accessibility concerns to be aware of. Some people might use assistive technology, such as screen readers, to access the content. Those users may have difficulty navigating or comprehending your presentation if the additional accessibility enhancements in this section are not applied. Both Microsoft and Google offer guidance specific to their tools, but here are some critical guidelines to remember.
Describing images
Adding text descriptions to images, commonly referred to as alt text, allows for users with screen readers to get a verbal description of the images in presentations. The alt text should describe the content and function of the image. Some examples include “Photo of a smiling woman” or “Logo and link to our home page.” Images that are decorative and do not provide any content or function do not need alt text. However, when unsure if an image is decorative or not, add some alt text.
Reading order
The order a screen reader reads a slide's contents is important. With a word processing document, the reading order is natural as the content generally proceeds from left to right and top to bottom. On a slide, however, content is added in separate text boxes that can be created or edited in any order. Sometimes the headings are at the bottom or side of a slide, but the intention is that they are read first. Imagine how confusing the content would become if it were read out of order.
Using the built-in slide layouts can minimize problems as they were designed to be accessible with reading order in mind. However, customizing or creating new layouts can lead to reading order adjustments being necessary.
Other considerations
In addition to adding alt text and adjusting the reading order of slide content, there are a few more aspects of a presentation that should be reviewed if it is going to be shared online:
- Make sure that links are clear and describe where the link will go. Avoid using only the words “Click Here”; opt instead to use the name of the website as the link itself.
- If your presentation includes video, make sure it has captions and, ideally, audio descriptions of the action. If captions are not an option, provide a link to a transcript.
- If your presentation includes audio, provide a link to a transcript.
- If you opt to save your presentation as a PDF, make sure to enable the setting to allow tags for accessibility to be created; otherwise, all the hard work will be for naught, and the PDF will not be accessible.
Using automated tools to check the accessibility of your presentation
It is clear by now that there are quite a few facets to making presentations accessible. Ideally, accessibility should be a priority throughout the design process. Waiting until the end to make changes and edits is more time-consuming and increases the likelihood of making errors.
There are automated tools that scan presentations to check for many things that may have been missed.
PowerPoint has a Check Accessibility tool, but for G Suite, you need to download an add-in. The most popular one is called Grackle.
These tools are a good first step to begin an overall review of your presentation but note that there are limits to what they will catch. For example, some software will place the URL to downloaded images into the alt text field. An automated scan would recognize that alt text was added to the image; however, that text would not be helpful to a screen reader user.
While it might seem like there is a lot to remember for accessibility, it’s easy to manage when you think about it at the beginning of your design process. Implementing accessibility will yield a presentation that everyone can access and enjoy.
Keith Casebonne
he/him/his
Technology and Communications Manager, Disability Rights Florida
Keith Casebonne is the Technology and Communications Manager at Disability Rights Florida, where he has worked for 17 years. As manager of both information technology and communications, Keith regularly works in social media, website development, graphic design, podcasting, network administration, computer security, and technical support. Digital accessibility is an area of special focus. Keith regularly speaks and writes about accessibility, security, and social media.
