Images and Complex Visuals
Images range from simple visuals—like photos or icons that only need short alternative or alt text—to complex visuals such as maps, charts, and diagrams that require more detail. Alt text provides a brief description so users with assistive technologies understand the image’s purpose.
For complex visuals, long descriptions offer a structured way to explain details that alt text alone can’t capture, ensuring equal access to meaning and context. This resource explains why alt tags and long descriptions matter, when to use them, and practical strategies for writing clear, effective descriptions that make visual content accessible for everyone.
Why is it Important?
Alternative text ensures that students who cannot see or interpret images still understand your content. By describing key elements and relationships, you provide equal access to concepts that visuals convey. This simple step makes learning inclusive and keeps every student engaged.
Quick Links
Creating Alternative Text for Images
Learn how to check images and graphics in your course materials, making sure they are designed for all students and users of your course content.
What Is Alt Text?
Alternative text (i.e., alt text) is the text equivalent of the image. It’s particularly important for presentations and documents in an online course or website viewed with a screen reader. Alt text describes the image to the user.
- Alt text is not the file name; it should describe the image and its relevance to content around it.
- If your image is complex (for example, a chart or diagram) and requires a lengthy description, add this description in the accompanying text within the same document or link to a separate document that contains the full text description. This practice is essential for students who use a screen reader and it will be helpful to other students too.
- How you use alt text in describing an image will depend on the context and how you define its purpose.
The Alternative Text section of the Getting Started with Accessibility guide has more information on how to create alt text for different types of images.
PowerPoint
Open a PowerPoint presentation that has images in it. You can add in alt text for images two different ways.
Select Picture Format. Then select Alt Text.

Microsoft PowerPoint will open a screen to add 1–2 sentences for alt text on the right side of the screen. If the image is simply decorative, define or describe it as such.

Right click on the image.
Click on Edit Alt Text.
The same screen will pop up on the right side of screen.
Good news! Adding alt text for other MS Office products (Word, Excel, etc.) is done exactly as it’s done in PowerPoint.
Google Slides
Open a Google Slides presentation with images.
Right click on the image. Options will pop up.

Click on Alt Text. A window will open. Type in 1–2 sentences describing the image.

More good news! Adding alt text for other Google products (Docs, Sheets, etc.) is done exactly as it’s done in Google Slides.
WordPress
Select Add Block and click the Image option. If no Image option appears, simply type “image” into the search bar.

You can upload an image from your computer, add one from your site’s media library, or add one using an external URL.
Select your image. A block formatting menu will appear on the right side of the page.

Enter your description in the Alternative Text field (located in the Settings section of your block formatting menu).

What if You Have a Complex Visual?
When your alt text cannot capture the full significance of the visual in 150 characters or less, you will have to provide a long description. A long description is a detailed text explanation of a complex visual, such as a chart, map, or diagram. It provides information that short alt text cannot capture, including relationships, trends, or context within the visual. Long descriptions ensure users with assistive technologies have equal access to the full meaning of visual content.
Write Your Long Description
When your alt text cannot capture the full significance of the visual, you will have to provide a long description. Whether you write them manually or use tools, the goal for long description is clarity, accuracy, and completeness so every learner can understand the concept without seeing the image.
As the content expert, you have the most context—so even if you use automated tools, you’ll need to review and update any generated text. When writing a long description by hand, include these key elements:
- Purpose of the image – Why is it included? What concept or data does it represent?
- Key elements – Describe important parts like labels, axes, colors, or sections.
- Relationships and trends – Explain patterns, comparisons, or connections between elements.
- Text within the image – Include any words, numbers, or legends that convey meaning.
- Context – How does this visual support the surrounding content or learning objective?
Start broad, then add details in a logical order. Use plain language and keep it clear. This method works in any platform that supports alt text or description fields, such as PowerPoint, Word, or Canvas.
Leverage AI tools like Copilot to generate a draft description quickly. Provide context about the image (e.g., “bar chart showing enrollment trends”) so the output is accurate. Always review and edit the draft for clarity and completeness before adding it to your content.
While Generative AI tools will differ slightly, use the following instructions for using Microsoft Copilot to generate a text description of your image.
Upload the image
- Go to m365.cloud.microsoft/chat.
- Sign in with your Microsoft 365 account.
- In the chat interface, click the “+” (Add content) icon.
- Select Add images or files.
- Use the file picker to upload the image from your computer.
- The image will appear as an attachment in your Copilot chat session
Prompt Copilot for a Long Description
- In the message box, type a clear instruction such as:
- “Generate a detailed long description of this image for accessibility purposes.”
- “Describe all significant elements in this image, including colors, labels, and context.”
- You can add extra context for better results:
- “Focus on geographic features and major cities in this map.”
- “Explain the relationships shown in this chart for students.”
For more information on writing for generative AI read: Write Effective Prompts.
Upload the image to a reverse image search tool to find existing descriptions or related information. This is helpful for maps, historical images, or widely used graphics. Verify accuracy and adapt the description to fit your learning context.
While browsers will differ slightly, use the following instructions for using Bing with Microsoft Edge to search and generate a text description.
Upload the image
- Open Microsoft Edge and go to bing.com/images.
- Click the camera icon in the search bar.
- Choose Browse and select the image file from your computer (or drag and drop it into the box).
Add a text description
- After uploading, Bing will show the image preview and a search box.
- In that search box, you can type additional text such as: “Describe the image in text” or any keywords that provide context (e.g., “map of North Carolina major cities”).
This helps refine the search results by combining visual recognition with text-based context.
Add Your Long Description
Once you’ve created a long description for your image, make it accessible by adding it to your course, website, or materials using one of the following methods. Be sure to provide a short alt text (e.g., See Long Description for Figure 2.1: Map of North Carolina below) and link or reference where the full description can be found.
Place the long description directly under the image.
This method requires no extra steps and ensures all users see the explanation.
Surround the image with the long description as part of the caption.
Useful for figures in documents or Canvas pages.
Give the page a clear title (e.g., Image Long Descriptions).
Use headings for each image:
H2: Image title
Paragraph: Long description text
Link to this page from the image’s alt text or nearby content.
- Create an online or downloadable doc titled Image Long Descriptions.
- Structure:
- H1: Document title
- H2: Each image title
- Paragraph: Long description
- Link the doc in your course materials.
Add in a text box near the image
Add to your Speaker Notes
In WordPress, insert the UNCG Details Block to add the details disclosure element to show or hide your description.
- In WordPress, click “+” to add a block.
- Select UNCG Details
- Add your image title text where the block says “Summary goes here…”
- Add your long description where the block says “Details go here…”
If you’re comfortable using the Canvas HTML editor, you can add the details disclosure element to show or hide your description.
- Use the <details><details> tag to wrap the widget
- Use <summary></summary> tag as your title
- Enter your text or other HTML elements after the closing </summary> tag and before the closing </details> tag.
This is an example of what a disclosure widget might look like in the HTML editor:
<details>
<summary>Flowchart Long Description<summary>
<p>This flowchart illustrates the prototyping process. It begins with brainstorming, followed by research, new product development, and trend analysis. The prototyping phase is highlighted in a pink diamond, and the design phase includes implementation and testing. Each section is color-coded—blue, orange, purple, and yellow—to distinguish steps.</p>
</details>
HTML Disclosure Widget Example
Whether you use the <details> HTML element to create a disclosure widget in WordPress or Canvas, they will look the same. Have a look at the following example. Click the title to show/hide the description.
Flowchart Long Description
This flowchart illustrates the prototyping process. It begins with brainstorming, followed by research, new product development, and trend analysis. The prototyping phase is highlighted in a pink diamond, and the design phase includes implementation and testing. Each section is color-coded—blue, orange, purple, and yellow—to distinguish steps.
Long Description examples
Check out the following examples of long descriptions. For additional examples explore the National Center for Accessible Media webpage Effective Practices for Description of Science Content within Digital Talking Books.

Flowchart Long Description: This flowchart illustrates the prototyping process. It begins with brainstorming, followed by research, new product development, and trend analysis. The prototyping phase is highlighted in a pink diamond, and the design phase includes implementation and testing. Each section is color-coded—blue, orange, purple, and yellow—to distinguish steps.

NC Map Long Description. This map shows North Carolina with major cities, highways, rivers, and lakes. Key cities such as Charlotte, Raleigh, Greensboro, Durham, and Asheville are labeled. Interstate highways including I-40, I-85, and I-95 are marked in bold lines. The map also highlights state boundaries with Virginia, Tennessee, Georgia, and South Carolina, and the Atlantic Ocean along the eastern edge.
Additional Resources
- Accessibility: Alt Text and Long Description (Penn State)
- Accessible Images (WebAIM)
- Alternative Text (WebAIM)
- How to Write Long Descriptions (MSU Denver)
- UDOIT (UNCG)
- Section 508: Alternative Text (Section508.gov)
Last Updated: December 11, 2025