Alt Text in Power BI: The Hidden Gem You Need to Use!

Okay, let’s be honest, Power BI’s new card visual isn’t exactly new anymore. But, like that book you bought ages ago and finally decided to read, I recently gave it some well-deserved attention. And let me tell you, it did not disappoint!

This visual has great features like dynamic formatting and the ability to add multiple fields in a single card. You can customise appearances, add rich text, and even include images and icons, making your reports both informative and visually appealing. One of the coolest discoveries was learning that Power BI lets you upload images AND add alt text for each one. Just check out the image below. In the Image Pane, you can easily select each image you uploaded and add alt text for it.

You might be wondering, “What is alt text and why should I bother with it?” Well, let me explain! Alt text, short for alternative text, is a simple yet powerful tool that helps people with visual impairments understand images. It’s a written description that screen readers read aloud, allowing users to grasp the meaning of a visual even if they can’t see it.

Imagine you’re reviewing a Power BI report full of charts, images, and key insights. If those visuals don’t have alt text, a screen reader will just skip them. That’s like listening to a podcast where the host keeps saying, “And as you can see here…” without ever explaining what’s on the screen. Frustrating, right?

Good alt text ensures everyone can access and understand the same data, making it an essential (but often overlooked) part of report design.

Alt text is also a crucial requirement for anyone adhering to the Web Content Accessibility Guidelines (WCAG) and ensuring compliance with accessibility laws.

Alt text falls under WCAG Success Criterion 1.1.1: Non-text Content, which states:

“All non-text content that is presented to the user has a text alternative that serves the equivalent purpose.”

In other words, if an image, including icons, conveys important information, it must have alt text that describes its purpose.

Alt text is a built-in accessibility feature in Power BI, but we, developers, need to configure it for each visual element on the page. We can follow WCAG best practices by ensuring that:

• Alt text is meaningful (describe what’s important in the image, not just “Chart” or “Image”).
• Alt text is concise (don’t over-explain—keep it short and relevant).
• Decorative images don’t need alt text (if an image is purely for design, leave alt text empty so screen readers skip it).

It’s important to note that alt text should be concise and have no more than 250 characters. If you’re unsure how to add alt text to your reports, here’s what you can do:

• Click on any visual in your report.
• Head to the Format pane.
• Look for the Alt Text option.
• Type a concise but meaningful description of what the visual represents.

For example, instead of writing:

“Line chart of sales data.”

Try this instead:

“A line chart showing monthly sales trends for 2023, with a steady increase from January to June and a peak in December.”

You can also use conditional formatting for alt text, which makes the process more automated. Another option would be:

“A line chart showing monthly sales trends for 2023. For more details, view the data table that is compatible with screen readers by pressing Alt + Shift + F11.”

Boom! Just like that, your report becomes far more inclusive. So, if you haven’t explored the card visual yet, now is the time! Here is a good tutorial to get you started Happy little accidents with the Power BI Card Visual. And while you’re at it, make your reports more accessible by adding alt text to your visuals. Your audience, both present and future, will thank you.

Thank you for joining me on this journey. Until next time, let’s keep crafting accessible insights that make a difference!