Whether you’re adding images to a blog post, service page or portfolio, writing descriptive alt text can improve the user experience, support accessibility and contribute to better search engine optimisation.
What Is Alt Text?
Alt text (alternative text) is a written description added to an image within your website’s code. It isn’t normally visible to visitors, but it provides valuable information for screen readers and search engines.
Good alt text should accurately describe what an image shows while fitting naturally with the content on the page.
Why Alt Text SEO Matters
Adding descriptive alt text benefits both your visitors and your website’s SEO.
It helps search engines understand your images, making them more likely to appear in Google Image Search and providing additional context about the page itself. While alt text isn’t one of the biggest ranking factors, it forms an important part of a well-optimised website.
If you’re investing in technical SEO, on-page SEO or improving your website’s accessibility, adding alt text should be part of your optimisation process.
Alt Text Improves Website Accessibility
Alt text plays an essential role in making websites accessible.
People who use screen readers rely on alt text to understand images that they cannot see. Without a meaningful description, important information may be missed, creating a poorer user experience.
Writing descriptive alt text also helps businesses work towards creating websites that are more accessible and inclusive for all visitors.
Alt Text Helps Search Engines Understand Images
Search engines cannot interpret images in the same way people can.
Instead, they use signals such as filenames, surrounding content and alt text to understand what an image represents. Well-written alt text provides additional context and can help your images appear in relevant search results.
This is why alt text SEO is considered a valuable part of on-page optimisation.
Alt Text Helps When Images Don’t Load
Occasionally, images fail to load because of a slow internet connection or a technical issue.
When this happens, alt text is displayed instead, helping visitors understand what should have appeared. It also ensures that your content remains meaningful, even if an image cannot be displayed.
How to Write Effective Alt Text for SEO
Writing effective alt text is straightforward if you follow a few simple guidelines.
- Describe exactly what the image shows.
- Keep the description clear and concise.
- Include your keyword naturally where it genuinely reflects the image.
- Avoid keyword stuffing or repeating the same phrase unnecessarily.
- Don’t begin every description with “Image of…” or “Picture of…”, as screen readers already identify images.
- Leave purely decorative images with empty alt text so screen readers can ignore them.
For example:
Instead of:
image1.jpg
or
Image of a plumber
Use:
Plumber installing a new boiler in a Berkshire home.
This provides useful context for both visitors and search engines.
Where to Add Alt Text in WordPress
Adding alt text in WordPress is simple.
Open the Media Library, select an image and complete the Alt Text field. If your website has been online for several years, there’s a good chance many of your existing images don’t include alt text.
Reviewing and updating older images is one of the quickest technical SEO improvements you can make.
Need Help Improving Your Website’s SEO?
If you’re unsure whether your website is missing alt text or other important SEO elements, I can carry out a technical review and identify opportunities to improve your site’s performance.
I provide technical SEO, WordPress support and website maintenance to help businesses improve their visibility in search engines while creating faster, more accessible websites.
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