The underrated img tag: How automated ALT text boosts Google rankings
Anyone looking for the big levers in marketing usually overlooks the small fields in the CMS. We’re talking about ALT text. Chronically underestimated, neglected or – due to a lack of time – often ignored altogether.
The problem? Although search engines are technically highly advanced in the age of computer vision, they still need context. They may recognise that there is a building in an image, but they don’t know whether it’s your client’s new, sustainably built corporate headquarters, a showcase project for modular construction, or a symbolic image relating to a completely different topic.
Without the exact textual context, the potential of your image SEO remains untapped.
The bottleneck in day-to-day content work: no time for detailed SEO tasks
For CMOs, SEO managers and content managers, this is often a question of resources. For small websites, manual maintenance may still work. But what happens in the case of a major relaunch or international multi-portal set-ups?
- The reality of day-to-day work: writing ALT text is an extremely fiddly and time-consuming task. When time is short, the field is either left blank, the CMS automatically pulls in the cryptic filename (IMG_4829.png), or a standard AI simply describes what’s visible without understanding the actual business context.
- The consequence: you lose valuable traffic from Google Image Search, miss out on your chances of securing the coveted spots in the Google Image Pack* and fail to address key accessibility issues (screen reader compatibility) .
* the coveted spots in the Google Image Pack (the image box directly within the search results)
The solution: Our SEO strategy makes automation smart
You don’t need to burden your content teams with weeks of assembly-line work. The solution lies in the intelligent combination of a strategic SEO concept and smart tool architecture, which makes this process fully automated, without the need for manual effort.
We have successfully achieved precisely this balance on large-scale projects such as Rhomberg (over 6,800 images across Germany, Austria and Switzerland) and Cteam (over 6,100 images in 9 languages ready for go-live).
The approach: we channel our SEO expertise into a bespoke concept. This feeds into the AI features of Sulu.ai so precisely that the ALT texts are generated in the background not as generic placeholders, but as highly context-specific and brand-relevant content. Quantity and quality are no longer mutually exclusive. And for the finishing touches? The content team can flexibly make manual adjustments at any time via the Sulu backend.
A key component of the overall strategy that makes all the difference
- Image SEO alone won’t boost your ranking, but when combined with a solid SEO strategy, it’s often exactly the piece of the jigsaw that puts you ahead of the competition.
- Optimised ALT text helps your images appear in search results whilst also strengthening the thematic relevance of the entire subpage.
Generate additional traffic
- Image search is an underestimated aspect of an overall SEO strategy.
- Optimised ALT text boosts images’ rankings in search results whilst simultaneously strengthening the thematic relevance of the entire subpage.
Greater visibility in the SERPs
- Only those who provide search engines with the exact context will appear in the visual snippets right on page 1.
Accessibility without extra effort
- Screen readers need precise descriptions.
- With our automated setup, your website is legally compliant and optimally accessible to all users.
Ready for AI search (GEO & LLMs)
- Modern response engines such as Gemini, Copilot, Claude and Perplexity crawl your website.
- Accurate ALT text helps these LLMs to correctly understand and link your visual content, and to present it to users as a visual source of answers.
Smart processes instead of manual, labour-intensive work
A well-structured SEO & GEO strategy, combined with a flexible CMS such as Sulu, ensures that your image database can realise its full potential without requiring significant internal effort.
Would you like to see exactly what success looks like after implementation? We’ll show you the setup in a 20-minute call.
Why are ALT texts important for LLMs and AI search engines such as ChatGPT, Perplexity and others?
- LLMs ‘read’ the web in text-based form: when a crawler from OpenAI or Perplexity scans your page to extract knowledge, it understands the content of an image much more quickly, accurately and efficiently if the context is provided directly in the ALT text.
- The source of visual responses: When a user asks ChatGPT, “Show me an example of modern C-parts management on a construction site”, the AI retrieves images from the web. How does it know what is shown in your image? From the ALT text and the surrounding context.
- Multimodal AI needs anchoring: even if LLMs can recognise images via computer vision, they use the ALT text for verification. It acts as the ‘single source of truth’ for website operators, ensuring that the AI does not misinterpret the image.
How do AI search engines use ALT text as a source of answers?
- When users search for visual examples or specific solutions using AI search, engines such as Perplexity or ChatGPT are increasingly generating responses that include images.
- The AI uses the ALT text (together with the surrounding text) to check whether the image matches the search query exactly. If the ALT text is missing or is purely generic, the image becomes ‘invisible’ to the AI and misses the opportunity to be featured as a visual recommendation in the generative responses.
