Alt text, short for “alternative text,” is a written description that conveys the content and function of an image. It is primarily used in HTML code to provide context when the image cannot be displayed or for screen readers that assist visually impaired users. Alt text plays a key role in digital accessibility by making visual content understandable to everyone, regardless of how they access it.
In addition to accessibility, alt text supports SEO by giving search engines more information about the image’s content. When written accurately and clearly, it helps improve how a page or post is indexed and can also impact image search rankings.
In social media, alt text serves the same purpose: it describes images in a way that makes them accessible to users who rely on assistive technologies. Most major platforms—like Instagram, Facebook, LinkedIn, and X—allow you to manually add alt text when uploading visual content. If not added manually, platforms may auto-generate it using image recognition, which is often inaccurate or too generic.
For creators and brands, writing your own alt text ensures your content is accessible, inclusive, and better understood by both users and algorithms.
Alt text isn’t just a technical feature—it’s a key part of ethical and effective content strategy. It helps people with visual impairments access your content, which is not only a good practice but often a legal requirement for digital content under accessibility laws and guidelines (such as WCAG).
On top of that, well-written alt text contributes to SEO. Search engines can’t “see” images, so they rely on alt text to understand what’s being displayed. This means your images (and the pages they live on) are more likely to show up in search results when the alt text is clear, descriptive, and relevant.
Effective alt text should be:
Here’s a poor alt text: "Dog on grass." Here’s a better version: "Golden retriever puppy lying on green grass with a tennis ball in its mouth."
While you don’t need to describe every detail, aim to convey what someone would need to know to understand the image in context.
Here’s how alt text is handled across major social media apps:
Adding custom alt text is a small step that reflects thoughtful content design and enhances user experience.
Q1: What is alt text? Alt text (alternative text) is a written description of an image used to improve accessibility and help users understand visual content.
Q2: How is alt text used in social media? It describes images for users who can’t see them, improving accessibility and sometimes aiding with platform visibility and reach.
Q3: Is alt text important for SEO? Yes. Alt text helps search engines understand image content, improving discoverability in image search and supporting overall page relevance.
Q4: Can I add alt text on all social platforms? Most major platforms support custom alt text for images, though the process varies slightly on each one.
