Alternative texts
Alternative text (alt text) is a text description of an image. It is not visible on the page, but it is read by search engines and screen readers used by blind and visually impaired users. Good alt text is therefore essential for both accessibility and SEO.
Where is the alt text entered?
The alt text is entered directly in the image settings:
- Open the "Text & Media" content element.
- Click the image in the media list to open its properties.
- Enter the description in the "Alternative Text" field.
- Save your changes.
Decorative images
A decorative image is an image that can be removed without any loss of meaning (e.g., a purely decorative image).
→ Leave the "Alternative Text" field empty
Example: A blue background banner that serves only a visual design purpose.
2. Functional Images (Links)
If an image functions as a link, the alt text should describe the link destination, not the image itself.
→ Alt text = description of the link destination
Example: A TUM logo that links to the TUM homepage → Alt text: "Go to the TUM homepage".
3. Informative images (most common case)
The image conveys information that is relevant to the content. Describe what the image shows in a factual, concise, and context-specific way.
Guidelines:
- Concise: Maximum of about 90 characters
- Objective: Avoid interpretations or opinions
- Relevant: Include only information that is important for understanding the page
- Direct: Start with the description itself, not with phrases like “This image shows...”
- No duplication: Do not repeat the image caption
Example:
Photo of a laboratory → Alt text: "Students using equipment in a TUM chemistry laboratory"
Avoid: "This image shows students in a laboratory."
4. Images containing text
If an image contains text (e.g., an infographic, diagram, or labeled screenshot), include the entire text content in the alt text.
→ Alt text = all relevant text that appears in the image