Creating Alt Text for Images

Alt text (alternative text) is a short-written description of an image that conveys the essential information or meaning for someone who can’t see it. It’s read aloud by screen readers and helps people who are blind or have low vision understand visual content. Alt text can also be valuable to sighted people,  particularly on webpages. If you have poor internet connection (such as in a rural area)  and can’t load the image, the alt text will load.

Tips for Writing Effective Alt Text:

• All images have alt text except for decorative images. This includes logos.
  • A decorative image is one used purely for visual appeal and decoration and does not provide any meaningful information. This could be an image of people with hands raised on the slide that reads “Q&A” or an image of a pushpin on a sticky note icon with the wording “Tips” next to a bullet that says Tips.
  • In some versions of Office, you can check the checkbox next to mark this image as decorative under the edit alt-text option. These images can be used for visual learners for visual engagement – but do not convey meaning.
• Be concise, but descriptive.
  • Aim for one sentence (under 150 characters if possible).
  • Include only what’s necessary to understand the image’s purpose.
• Create additional resources if needed
  • If the image is providing important information and requires a longer description the developer should create a separate document with this information and link to this in the document.
• Use present tense and active voice.
  • “A woman holds a guide dog harness” is better than “A woman is holding…”
• Focus on meaning, not every detail.
  • Ask: Why is this image here? What message is it conveying?
• Don’t start with “Image of…” or “Photo of…”
  • Screen readers already announce that it’s an image.
• Context matters.
  • Tailor the description to the surrounding content. The same image might need different alt text in different settings.
• Text boxes should not be used, as they cannot be equally accessed by all screen-readers.
• Customize Alt Text
  • It is better to write your own alt text, rather than allow Word to automatically generate it for you, if you have this option. The automatically generated descriptions are generally not accurate.