Alt attributes, often referred to as alt tags or alt texts, are an essential part of web pages that is often overlooked. They play a crucial role both for the accessibility of your website and for search engine optimization (SEO). In this article, you will find out what alt attributes are, why they are important and how you can make the best use of them.
Definition and syntax #
- What are alt attributes? An alt attribute is a specification within an image tag in HTML that provides alternative text for an image. This text is displayed if the image cannot be rendered in the browser and is also useful for screen readers.
- HTML syntax: An alt attribute is inserted directly into the image tag:
<img src="image.jpg" alt="Beschreibender Text zum Bild">.
Functions and use cases #
- Accessibility: Alt attributes improve web accessibility by enabling screen readers to convey the content of images to users with visual impairments.
- Fallback for missing images: If an image fails to load due to a broken link or a slow connection, the alt text provides a description of the image.
- SEO and image indexing: Search engines use alt attributes to understand and index the content of images, which can improve the visibility of a page in image search results.
Best practices for writing alt texts #
- Descriptive and concise: Alt texts should describe the image content precisely and concisely and be contextually relevant to the content of the page.
- Avoid keyword stuffing: Including relevant keywords is beneficial, but overusing them can be harmful and is considered spammy by search engines.
- Use for meaningful images: Alt text should be used for images that convey information or meaning on the page. Decorative images that do not add an informative value can have an empty alt attribute (
alt="").
Effects on SEO #
- Image SEO: Proper use of alt attributes can improve a website’s SEO by providing search engines with additional context for images.
- Page SEO: Although alt texts are mainly used for accessibility and image indexing, they can also contribute to the overall SEO of a page by reinforcing the thematic relevance of the content.
Implementation in content management systems #
- CMS integration: Most content management systems, such as WordPress, offer fields for entering alt text when uploading images, making it easier for webmasters to include this attribute without directly editing the HTML code.
Summary #
Alt attributes are a critical part of web development that improves both accessibility and SEO. By implementing clear, descriptive alt text, you can ensure that all users, regardless of their ability to see images, can understand the content of your website. They also help search engines to index your images correctly, which contributes to the visibility of your website in search results.
FAQ #
What is an alt attribute? An alt attribute is an HTML attribute within a <img> tag that describes the content and function of an image on a web page.
Why are alt attributes important? They are important for web accessibility as they provide a textual alternative for users and search engines if the image is not available or cannot be displayed. They are also crucial for image SEO.
How do I write good alt texts? Good alt texts are descriptive, concise and avoid keyword stuffing. They should be used for meaningful images that convey information or meaning on the page.
Sources:
https://www.conductor.com/de/academy/glossar/alt-attribut/
https://www.semrush.com/blog/alt-text/
https://en.ryte.com/wiki/ALT_Attribute
https://keyperformance.de/alt-tag
https://www.innovationvisual.com/knowledge/why-image-alt-text-is-important-for-seo