Alt Text

Alt text, or "alternative text," is a brief description added to images on websites and social media posts.

It has two main purposes:

Accessibility: Alt text helps people who use screen readers understand the content of images.
SEO: It provides search engines with information about the image, which can help improve your content's visibility in search results.

Using alt text makes social media more inclusive by allowing everyone, including visually impaired users, to engage with your content. Additionally, it enhances your brand’s online presence by helping search engines understand your images.

Alt text improves accessibility on social media by allowing visually impaired users to engage with image content through screen readers. Adding alt text also supports SEO on social platforms, helping to boost your visibility in searches. Instagram and Twitter offer options to add alt text, making it easy to take this inclusive step with each post.

By including alt text, you create a more accessible social media experience, reach a broader audience, and improve content performance.

Best practices for writing alt text

Good alt text enhances both accessibility and user experience. Here are some tips:

Keep it brief: Aim for 1-2 concise sentences.
Be specific: Describe key elements and the purpose of the image.
Include relevant keywords naturally.
Avoid saying “image of” or “picture of”.
Identify unique image types, like logos or illustrations.

For social media, describe the mood and key elements in the image. Instagram allows alt text additions to images, so use descriptive details to make your posts more accessible.

Common mistakes to avoid

When creating alt text, watch out for these pitfalls:

Keyword stuffing: Avoid cramming keywords solely for SEO, as this detracts from readability and accessibility.
Using phrases like “image of”: Screen readers already indicate it’s an image.
Leaving alt text blank: Empty alt attributes don’t provide any value for users with visual impairments.
Over-describing: Keep descriptions focused on key details and avoid unnecessary words.
Repeating surrounding text: Alt text should complement, not duplicate, nearby text.
Including emojis: These may confuse screen readers and don’t add useful information for visually impaired users.

How alt text helps SEO

Alt text helps your SEO by making images more discoverable in search engines. By adding descriptive alt text to images, you provide search engines with valuable context about the image. Since search engines can’t “see” images like humans can, alt text acts as their eyes, helping them understand and index your content more effectively.

Good alt text can also help images appear in image search results, making your content more accessible and searchable.

Example of bad alt text

Bad alt text is often too vague or uninformative. For instance, using “image001.jpg” or “photo of a person” doesn’t provide enough detail.

A good alternative would be “A woman holding a cup of coffee while sitting at a desk” which offers more context.

Alt text rule of thumb

Alt text should be clear and concise, focusing on essential details of the image. A general guideline is to keep it between 5-15 words, aiming to be specific without overloading the description.

When should you avoid using alt text?

Not all images need alt text. For purely decorative images, like background patterns or decorative icons, you can leave the alt attribute empty (alt="") so screen readers skip over it. This keeps users focused on meaningful content.

What happens if alt text is missing?

Without alt text, visually impaired users can’t understand the image content, and search engines can’t index it effectively. Missing alt text reduces both accessibility and SEO, so it’s always best to include it for images with meaningful information.

How long should alt text be?

Alt text should be concise but descriptive, generally around 5-15 words. The goal is to clearly describe the image's content and purpose without overwhelming screen reader users with too much text.