Control Alt Achieve: AI for Alt Text: Boost Accessibility with this Prompt

Illustration of a computer with alt text beside the heading "A.I. for Alt Text" and subheading "Boost Accessibility with this Prompt" for ControlAltAchieve.com by @ericcurts

Did you know that 285 million people worldwide have vision impairments?

Anytime I share content online, I want to make sure it reaches as many people as possible. If that content includes images, that can be a challenge for readers who have difficulty with the pictures.

One way to help with this is by using "alt text".

Alt text is a short description of an image that helps people who can't see it understand its meaning. When someone uses assistive technology, such as a screen reader, it will read the alt text aloud.

This is so helpful, but it can be a challenge to write good alt text that aligns to guidelines and best practices, especially if you share a lot of content online.

To help with this I have created a prompt you can use with your favorite AI chatbot to generate alt text for images in your social media posts. See below for directions, examples, and a copy of the prompt to use however you need. As always please share your suggestions for improvement.

📋 Your Ready-Made AI Prompt

Below is the prompt you can use with a chatbot such as ChatGPT or Gemini. Feel free to copy, modify, and use this prompt however you need. This prompt template is designed for alt text for a social media post, but you could adapt it for any sort of online image as needed.

For this interaction, your purpose is to generate "alt text" for an image that will be used in a social media post. You will generate three different versions for me to select from.

I will upload the image and enter the text that will accompany the image in the social media post.

Before generating the three alt text versions, analyze the image and the accompanying text I provide. Consider the primary purpose of the image in the context of the social media post: Is it illustrative, informative, decorative, or meant to evoke a specific emotion? If the image, accompanying text, or the image's relevance to the post is ambiguous, or if you need more context (e.g., about the intended audience or the key takeaway message), please ask me clarifying questions to ensure you can generate the best alt text possible.

When generating the alt text, follow these suggestions as provided by the Section 508 guidelines:

- Alt text should be short and to the point.

- Alt text should communicate the same information as the visual content.

- Alt text should refer to relevant content provided by the image, rather than simply describing how the image looks. Focus on what's important for understanding the image's contribution to the post.

- Alt text should not contain any extra or unnecessary information, and should not repeat information that is already provided in the text.

- Alt text must be in the same language as the main content. For example, if you translate an English document into Spanish, you must also translate the alt text into Spanish.

In summary, you will use the image I will upload, the accompanying text I will enter, any clarifications we discuss, and the Section 508 guidelines listed above to generate three versions of appropriate alt text.

Are you ready for me to upload my image and enter my accompanying text?

1️⃣ Real-World Example 1

As a first example, here is an image I shared online from when I presented at the Raising Student Achievement Conference:

Bearded presenter Eric Curts sits at a conference table with his Chromebook open, animatedly addressing a room of educators.

And here is the content I included in the social media post:

Fantastic day at the Raising Student Achievement Conference with so many amazing educators! I presented on AI for personalized student learning & feedback, EduProtocols, & accessibility tools. Access all my session resources at https://www.controlaltachieve.com/2024/12/my-2024-rsac-sessions.html

When I used the prompt with different AI chatbots, here is the alt text that each generated:

ChatGPT

Eric Curts seated behind a table with a white laptop, gesturing as he speaks to educators at the Raising Student Achievement Conference.
Bearded presenter Eric Curts sits at a conference table with his Chromebook open, animatedly addressing a room of educators.
A speaker (Eric Curts) gestures from his chair behind a laptop, engaging conference attendees in a dimly lit meeting room.

Gemini

A presenter, seen from the audience's perspective, seated at a table with a laptop, actively speaking and gesturing during a conference session.
Man at a conference speaking to attendees, with an open laptop on the table in front of him.
Speaker engaging with an audience during a presentation, seated at a table with presentation equipment.

2️⃣ Real-World Example 2

As a second example, here is an image I shared online from when I shared a new blog post about using AI to generate interactive "Choose Your Own Adventure" stories.

Two-page book layout on wood: left page displays a branching choice diagram labeled A, B, and C under the question “Do you open door A, B or C?”; right page proclaims “AI for CYOA Stories,” with “@ericcurts ControlAltAchieve.com” at the bottom.

And here is the content I included in the social media post:

Door A, B or C? Using AI for Interactive Choose Your Own Adventure Stories - https://www.controlaltachieve.com/2025/04/ai-cyoa.html

📑 CYOA Prompt Template & Directions

🐝 Example - Life of a Bee

📗 Example - The Giver

🐂 Example - Oregon Trail

👦 Individual Option with SchoolAI

When I used the prompt with different AI chatbots, here is the alt text that each generated:

ChatGPT

Open-book graphic: left page asks “Do you open door A, B or C?” above green, blue, and yellow A-B-C circles linked to branching arrows; right page shows “AI for CYOA Stories” in bold colored text, with “@ericcurts ControlAltAchieve.com” at the bottom.
Illustration of an open notebook: left side features the prompt “Do you open door A, B or C?” with three colored choice icons and arrows; right side reads “AI for CYOA Stories” in large blue, black, yellow, and green lettering, plus the author handle and website below.
Two-page book layout on wood: left page displays a branching choice diagram labeled A, B, and C under the question “Do you open door A, B or C?”; right page proclaims “AI for CYOA Stories,” with “@ericcurts ControlAltAchieve.com” at the bottom.

Gemini

Image styled as an open book. Left page asks 'Do you open door A, B or C?' above graphical A, B, C choices. Right page reads 'AI for CYOA Stories'. Features ControlAltAchieve.com by @ericcurts.
An open book visually illustrates the theme of 'AI for CYOA Stories,' presenting 'A, B, C' choice options alongside the blog post's title and ControlAltAchieve.com branding.
Graphic of an open book illustrating 'AI for CYOA Stories' with 'Door A, B or C?' decision paths. From ControlAltAchieve.com.

💎 Bonus: Save Time with Gems

Because this is a process that I need to do frequently, I ended up creating a custom "Gem" with Gemini. Gems are customized prompts that you can use repeatedly to save time on repetitive tasks. This feature is free to all users.

From Gemini - https://gemini.google.com/ - you can click on the "Explore Gems" option in the left menu.
Next click the "New Gem" button.
Then fill in a name for the Gem, and then paste in the alt text prompt in the "Instruction" section.
As a bonus I also used the "Knowledge" section to upload more resources about alt text including PDF versions of these sites - Resource 1 - Resource 2 - Resource 3
Finally click "Save" when done.

Screenshot of creating a custom Gem in Gemini for alt text

You can now access and use this Gem anytime you need. Because the prompt is already entered, you can simply upload your image and paste in the text of your post, and the Gem will generate your alt text.

💬 Using Alt Text when Posting

Now that you have the alt text you want to use, you can easily add it to any of your social media posts. When posting on any platform (Bluesky, LinkedIn, X, Facebook, etc.) you will find an alt text link for any image you upload.

Screenshot of the alt text link when creating a Bluesky social media post

Simply click on the alt text link and paste in the content. This will add the alt text to the image so that screen readers can access it when needed.