Why an accessible site works for SEO and GEO, not just for people

In short: making a website accessible doesn’t only serve the people who use assistive technologies. The same work that helps a screen reader read a page helps Google index it and helps generative engines like ChatGPT, Perplexity and AI Overviews understand it and cite it. We explain where accessibility and SEO genuinely overlap, where instead they diverge (because accessibility isn’t a magic ranking lever), and why the new frontier of citability by AI rewards exactly the things an accessible site already does well.

When we took on the digital project for Olinda, the social enterprise founded in 1996 in the spaces of the former Paolo Pini psychiatric hospital in Milan, the challenge wasn’t technical but one of legibility. Olinda is an ecosystem that weaves together work inclusion, hospitality, food service, culture and urban regeneration, with distinct entities like Jodok, OstellOlinda and TeatroLaCucina, each with its own identity. Audiences far apart from one another (donors, companies, theatre-goers, hostel guests, people looking for support) had to be able to quickly find their own way inside a complex system.

That demand for clarity, worked through in the strategic workshops and translated into a precise information architecture, produced an interesting side effect. The site that makes an ecosystem understandable to a person is the same one that makes it understandable to a machine. That’s where this article starts: from the point at which accessibility, SEO and generative AI stop being three separate topics.

What we mean by an accessible site (and what we don’t)

Web accessibility doesn’t only mean “compatible with a screen reader”. It means designing pages that anyone can perceive, understand and use, regardless of device, connection or sensory and motor abilities. The international reference guidelines are the W3C’s WCAG, and since 28 June 2025 the European Accessibility Act has made the topic an obligation for a far wider range of companies than before.

In practice, an accessible site rests on a few concrete things: a coherent heading structure that organises content into a logical hierarchy; descriptive alternative text on images; sufficient colour contrast between text and background; full keyboard navigation; and meaningful labels on links, buttons and fields. These are choices about the substance of the code and the content, not a decorative layer added afterwards. And that’s exactly why they have effects well beyond accessibility.

Where accessibility and SEO shake hands

The overlap between accessibility and search engine optimization isn’t a lucky coincidence: it comes from the fact that a screen reader and a Google crawler read a page in more or less the same way, that is, from the code and not from the visual appearance.

Semantic headings and document structure

The same <h1>, <h2> and <h3> that let a screen reader user jump from one section to another tell Google’s crawler what the hierarchy of topics on the page is. A clean heading structure is at once an accessibility requirement and a signal that helps engines understand what a document is about and which parts matter most.

Alt text and readable content

An image’s alt text exists to describe to those who can’t see it what it represents. But that same text is also the only way Google has of “reading” an image and surfacing it in image search. In the same way, content written as real text (not embedded inside a graphic or generated only via JavaScript after loading) is at once more accessible and more indexable. When in the Olinda project we structured the organisation’s key figures as hierarchical text instead of as images, we did it for accessibility reasons: the benefit for indexing came as a gift.

Performance and navigation

A lightweight site, one that loads quickly even on a slow connection, is more usable for those with limited bandwidth and is also a site that Google measures as a good page experience. It’s the same ground as the Core Web Vitals that Google collects on real users: loading speed, visual stability and responsiveness aren’t only SEO metrics, they’re the conditions that make a site usable by everyone.

Where accessibility and SEO really diverge

Here comes the part that the optimistic guides on the subject prefer to skip. Despite all these overlaps, it’s wrong to say “make the site accessible and you’ll climb on Google”. Accessibility isn’t a direct ranking factor: Google doesn’t award points because a button has a well-written aria-label or because the contrast meets the ratio required by WCAG.

The proof is that the two things can exist separately. There are sites that are technically very accessible and effectively invisible in search results, because the content is weak or nobody is searching for it. And there are sites full of accessibility barriers that rank very well, because they answer a question better than anyone else. Accessibility and SEO overlap in the technical “how” (semantic structure, readable text, performance), but they pursue different goals: one wants to make the site usable by everyone, the other wants to make it relevant to a query.

To put it bluntly: accessibility improves the technical foundations SEO works on, but it doesn’t replace the editorial and strategic work that genuinely makes the difference in ranking. It’s a multiplier of valid content, not a substitute for it.

GEO rewards what SEO ignores

If on the SEO front accessibility is a side benefit, on the GEO front (Generative Engine Optimization, that is, citability by generative engines like Google’s AI Overviews, ChatGPT or Perplexity) it becomes something more: a direct advantage. And here we’re not speaking hypothetically. We verified it on Olinda’s site.

We asked an AI agent, the same kind of technology that today browses the web in place of people, to visit olinda.org and carry out some concrete tasks: find out what the organisation does, open the menus, follow the calls to action, reconstruct the relationship between the different entities of the ecosystem. It’s the way a generative system “explores” a site before summarising it or citing it in an answer.

The agent completed the tasks without difficulty, and the reason is instructive. To orient itself, a system like this leans largely on the page’s accessibility tree, that is, the same semantic structure the browser exposes to assistive technologies and that a screen reader relies on. Where that structure is clear, the machine understands; where it’s confused or exists only as a visual effect, it gets lost.

What the agent reconstructed is telling. The navigation bar exposes a clearly labelled “Olinda ecosystem” section with named links to the vertical brands. The main menu has meaningful items (About us, What we do, Services for companies, How to support us), and the mega menus open on click revealing real links to descriptive URLs like /inserimenti-lavorativi/ and /cultura-e-formazione/, not anonymous elements generated only via JavaScript. There’s a “Skip to main content” link, the heading hierarchy tells the organisation of the content section by section, the images have real text descriptions and even the organisation’s key figures are structured text, not graphics.

This is the point. A generative engine that has to decide whether to cite a source prefers what it can extract and understand with certainty: clean semantic HTML, clear hierarchies, explicit relationships between concepts, content as text. These are exactly the characteristics that define an accessible site. An accessible site is, literally, a site more readable by a machine that has to understand it in order to talk about it. Where classic SEO ignores the semantic quality of the markup, GEO rewards it, because it’s the raw material with which a language model reconstructs the meaning of a page.

Behind the scenes: how we approach it at PaperPlane

This legibility isn’t achieved at the end of a project. It’s born at the start, in the strategic workshops we begin with. For Olinda it was there that we redefined the information architecture, answering a simple question: how do you make a complex system legible without generating cognitive overload? The answer, a clear hierarchy that separates identity, paths, projects, services and donations, is the same structure a machine then travels through without getting lost.

On the visual side, semantic coherence and contrast were explicit requirements, not finishing touches. Every brand colour in the project was validated to guarantee an adequate minimum contrast against the background, so as to remain distinguishable even for those with visual difficulties. On the technical side, the whole ecosystem is built on WordPress in a multisite configuration, resting on our Flying infrastructure: a single lightweight theme, reusable components with consistent markup, and hosting on Kinsta to serve pages quickly. Less weight, a cleaner structure, the same logic applied to every node of the ecosystem. It’s an approach that works at once for the user, for the crawler and for the LLM.

A real limitation: accessibility isn’t “added” at the end

The most popular shortcut, and the riskiest, is accessibility overlays: “one-click” widgets that promise to make an existing site compliant with one line of code and a floating menu that adjusts contrast and text size. They look like the perfect solution at zero cost. In practice, they rarely solve structural problems (a missing heading stays missing, an image without alt stays mute to the screen reader) and in several cases they worsen the real experience of those who use assistive technologies, getting in the way of how they work. Accessibility, like the parsability GEO needs, is decided in the initial architecture, not in a patch applied on top.

There’s also a subtler honesty to keep in mind: accessibility and readability by AI are an ongoing path, not a badge you earn once and for all. Even a well-built site contains choices to weigh continually. When on Olinda we added a decorative element that scrolls through the links to the ecosystem’s brands on a loop, we hid it from assistive technologies and removed it from the keyboard navigation order, so that a screen reader reads it once instead of stumbling over dozens of repetitions. It’s the kind of detail automated audit tools can’t assess and that requires a conscious decision, taken case by case.

Three fronts, one job

We say it often when talking about performance: speed, accessibility and sustainability are the same problem seen from different angles. With SEO and GEO the picture is complete. A well-written heading serves the screen reader, Google’s crawler and the model that generates an answer citing the source. Content as real text is at once accessible, indexable and citable. A lightweight page consumes less energy, loads faster and offers a better page experience.

These aren’t five different jobs to line up and fund separately. It’s a single underlying quality, comprehensibility, demanded by five different interlocutors: the person, the screen reader, the search engine, the generative model and the planet. The companies that took web accessibility seriously first discovered this convergence before the others.

Where to start if you have a site to make more legible

1. Navigate your site without looking at it. Turn on the screen reader built into your operating system (VoiceOver on Mac, Narrator on Windows) and try to reach the three most important pages using only the keyboard. If you get lost, a machine gets lost too.
2. Check headings, alt and contrast. These are the three areas with the best effort-to-result ratio. A free tool like axe DevTools gives you a first snapshot of the most obvious problems in a few minutes.
3. Verify that the key content is text. Open an important page and check that the decisive information (who you are, what you offer, how to contact you) is real text and not enclosed inside images or loaded only after interaction. It’s what makes content indexable and citable.
4. Start from the architecture, not the details. If the content structure is confused, fixing twenty alt texts won’t move the needle. A clear map of sections and hierarchies is the foundation everything else depends on, for people and for machines.

If you want a site that works on every front

Making a site accessible isn’t a cost to justify with regulatory compliance alone: it’s an investment that works at the same time for people, for ranking and for citability by AI. The starting point is almost always an honest audit, one that looks at the real structure of the site and says where the barriers are, without promising badges.

If you want to understand where to begin, at PaperPlane we offer a consultation dedicated to digital accessibility: a first audit to assess the level of your site and the concrete room for improvement. If you need help, we’re here.