Alt text, short for "alternative text," is used to describe images on websites and social media. Its primary purpose is to provide a text-based alternative to an image for users who cannot see it, whether due to visual impairments or technical issues like slow internet. When an image doesn’t load, alt text will appear in its place, describing what the image is about.
Alt text is crucial for accessibility and SEO. For visually impaired users who rely on screen readers, alt text helps them understand the content of an image. It also helps search engines index your content, making your site more discoverable. Essentially, alt text ensures that everyone can access the content of your website, regardless of how they’re viewing it.
Typically, alt text isn’t visible on a webpage unless the image fails to load, or a user is using a screen reader. However, anyone can check the alt text by looking at the page’s HTML code or using accessibility tools.
Yes, alt text is absolutely worth it! Not only does it improve accessibility for people with disabilities, but it also boosts your SEO by helping search engines understand the context of your images. Adding descriptive alt text makes your content more inclusive and searchable.
Bad alt text would be too vague or unhelpful. For example, writing “image001.jpg” or “photo of a person” doesn’t provide enough context. Good alt text should be descriptive and specific. For instance, “A woman holding a cup of coffee while sitting at a desk” is much more informative.
Alt text should describe the image in a clear, concise manner. It should focus on the important details relevant to the content. A good rule of thumb is to keep it between 5-15 words and make it specific. Alt text is about helping the user understand the image, so avoid writing too much or too little.
Not every image requires alt text. Decorative images or icons that don’t add meaning to the content, such as a decorative background, can be left without alt text. In this case, you can use an empty alt attribute (alt="") so screen readers skip over it without confusing the user.
If alt text is missing, visually impaired users won’t be able to understand the context of the image, and search engines won’t be able to properly index it. This can hurt both accessibility and SEO, so it’s always best to include alt text whenever an image conveys important information.
Alt text should generally be concise but descriptive. Aim for around 5-15 words that clearly describe the image's content and purpose. There’s no hard limit, but longer descriptions can become cumbersome for screen reader users.
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