Web Accessibility: Alt Text Best Practices

Alternative text (alt text) provides an accessible description for images within web content, enhancing accessibility for users with visual impairments or those navigating the internet without images.

Alt text should accurately reflect the content and function of an image. If it doesn't convey anything meaningful, use an empty alt attribute (alt="").

An image's function is based on its purpose within the webpage. It might be a link to another page, a decorative element, or a part of a figure.

If an image is a clickable link, its alt text should clearly describe the link's destination or purpose. This helps users understand where they will be directed.

If an image's content is described in the surrounding text, a minimal alt text like "alt="" can be used. This indicates the image is visually redundant.

Avoid using redundant or overly descriptive alt text. For example, "Image of Ellen Ochoa" is unnecessary when the image is of Ellen Ochoa.

Alt text should be concise and focus on the image's content and function. Avoid adding extra details that are not relevant to the image itself.

Alt text helps make web content accessible for users with disabilities, promotes inclusivity, and improves search engine optimization (SEO) by providing a clear description of the images.

Describing the function of the linked image, especially for screen reader users who navigate by links.

Alt text is essential for screen readers to understand the content and function of a linked image, especially when the image is the only content within the link.

If an image presents content that is not conveyed by surrounding text, include a brief and accurate description within the alt attribute.

When an image is purely decorative and does not convey any content, using empty alt text (alt="") is appropriate.

When an image is only used for decorative purposes, it's best to remove it from the page content and define it as a CSS background image.

The alt attribute should describe the function of the button, such as 'Search', 'Submit', 'Register', or 'Place your order'.

The main image's alt attribute should describe the content presented within the image that is not conveyed by the image map hot spots.

Each hotspot in a client-side image map must have an equivalent alt attribute, describing its corresponding content.

Server-side image maps, which interpret mouse click coordinates on the server side, are not perceivable by screen readers and should be replaced with client-side image maps.

CSS images should be used for decorative images that don't require alt text.

Images that convey content should be within the page markup, not defined in CSS.

When background images present content, that content must be made accessible within the page markup, as it's not possible to add alt text directly to CSS or background images.

Form image buttons that merely present rasterized text should be replaced with true text, styled with CSS as desired.

It conveys the purpose of the image, such as its link destination or if it is purely decorative.

When an image's content is adequately described in the surrounding text, an empty alt attribute (alt="") can be used to indicate visual redundancy.

Instead of relying solely on a long description, provide a succinct and informative alt text, and then link to a separate page with a more detailed explanation.

The best alt text will depend on the context and the intended content of the image.

The element, designed to contain an and a , should have alt text even if it's described in the figure caption.

If alt text is written effectively, it can create a more accessible and inclusive web for users with visual impairments.

While the element is a great way to structure content, remember that the still needs alt text to ensure proper accessibility.

Implementing alt text correctly is a crucial step towards creating a more accessible web, providing users with visual impairments a better experience.