What Is Alt Text? Why It Matters & How to Write It
What Is Alt Text? Why It Matters & How to Write It
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Author: Rachel Handley
6 min read
July 14, 2025
Contributor: Cecilia Meis
What Is Alt Text?
Alt text, or alternative text, is text that describes an image and appears in the image’s place if the image fails to load.
It also serves as a description for screen readers.
Take this blog post example:
And this social media post by Matt Ramsey:
Why Alt Text Matters
Alt text matters because it:
- Makes your images more accessible: It helps users who can’t see images understand their content, either by reading the text or hearing it through a screen reader
- Helps your images appear on relevant search results: Search engines use alt text in part to understand images and rank them in relevant search queries, which is a goal of image SEO
How to Add Alt Text
Here’s how to add alt text to an image uploaded to a website content management system (CMS) or social media platform.
In your CMS, open the page with the image in the page editor. Switch to the code editor, and then add the alt attribute to the image’s HTML tag.
Like this:
<img src=“image.jpg” **alt=“Alt text goes here”**>
Alternatively, click the image to open its settings. Add your alt text to the alt text setting.
In WordPress, the alt text setting looks like this:
When posting an image on a social media platform, look for the platform’s alt text setting. Select it, enter your alt text, and continue the image upload process.
Here’s how the alt text setting looks for a LinkedIn post:
6 Alt Text Best Practices
Follow these six best practices to improve your alt text’s effectiveness:
1. Be Descriptive
Alt text should clearly describe the image, providing enough detail so users understand its content.
For example, Lush’s bath bombs product page uses product names as the images’ alt text:
2. Keep It Short
Alt text should be concise—ideally under 125 characters—so users and screen readers can quickly read it.
3. Include Relevant Keywords
Include relevant keywords in your alt text to help search engines rank your images.
4. Don’t Use Alt Text for Decorative Images
Use a null alt attribute to tell screen readers to ignore decorative images. Like this:
<img alt="" src="decorative-image.jpg">
5. Localize Alt Text
Localize your alt text to match the cultural and linguistic context of your audience.
6. Audit Alt Text Regularly
Regularly audit your alt text to identify and act on opportunities for improvement, and ultimately help your images rank better in search results.
Use AI to Speed Up Alt Text Generation
AI can significantly speed up alt text generation, especially when you need to write alt text for many images.