Google can't look at a picture the way a person does. It relies on surrounding text, and especially the image's alt text, to decide what an image is about and when to show it in search results.
How alt text helps your rankings
- Google Images traffic: well-described images can appear in image search and bring visitors.
- Page relevance: descriptive alt text reinforces what your page is about.
- Accessibility signals: accessible, high-quality pages tend to perform better overall.
- Linked images: when an image is a link, its alt text acts like the link's anchor text.
What about image titles and captions?
Titles show as a tooltip when someone hovers over an image, and captions are visible text under it. Captions are read by both visitors and search engines, so a short, natural caption adds context. Image titles have little direct SEO weight but improve the experience.
Common mistakes
- Leaving alt text empty on important images
- Using file names like
DSC_0012 - Stuffing keywords: Google treats this as spam
- Copying the same alt text onto every image
The chart blind spot: why search engines miss your data
A chart saved as a JPG or PNG is just pixels. Search engines can't reliably read the axis values, data points or trends inside it, so the most valuable information on a report or infographic page is effectively invisible to them.
- Alt text gives a short summary of what the chart shows, which is useful but limited to around 150 characters.
- A caption or description explains the key trend in plain language that crawlers can index.
- An HTML data table turns the raw numbers into real, crawlable text that search engines can parse and may quote in results.
Alt Text Meta extracts the data from your charts and generates an accessible HTML table and trend summary you can place beside the image (in WordPress, via the [chart_table] shortcode).
Alt text won't fix rankings on its own
Be wary of anyone promising alt text will push you to the top of Google. It's one signal among many. What it does do is make your pages accessible and easier to understand, for screen-reader users and for search engines, and that supports image search visibility, page relevance and user experience.
Automating it in WordPress
Most sites have hundreds of images with missing alt text. Alt-Text-Image-Meta scans your Media Library, analyses each image with AI, and fills in alt text, title, caption and description, so every image works for your SEO without hours of manual typing.