Web accessibility means a website can be used by everyone, including people with visual, hearing, motor or cognitive disabilities. The international standard, WCAG (Web Content Accessibility Guidelines), defines how to achieve this under four principles: perceivable, operable, understandable and robust. An accessible site isn’t just the right thing to do; it also strengthens your SEO, widens your audience and is a legal requirement in many countries. Building accessibility in from the start is an inseparable part of our web development services.
The Four Principles of WCAG (POUR)
- Perceivable: content must be perceivable by everyone — alt text for images, captions for videos, sufficient color contrast.
- Operable: the site must be fully usable by keyboard, not just mouse; no traps.
- Understandable: text must be readable, navigation consistent, and form errors clearly explained.
- Robust: content must work reliably with assistive technologies, including screen readers.
Why Accessibility Isn’t Just "Goodwill"
Accessibility has concrete business benefits. Roughly one in six people worldwide lives with some form of disability — an inaccessible site shuts out that huge audience directly. Better still, most accessibility improvements (meaningful heading structure, alt text, fast and keyboard-navigable pages) directly strengthen SEO too; they line up exactly with the signals Google values.
Accessibility and SEO are largely two sides of the same job: adding alt text helps both screen readers and Google; a meaningful heading hierarchy guides both assistive tech and search engines. An improvement you make for one usually improves the other.
Semantic HTML: The Foundation of the Foundation
The biggest part of accessibility comes from using the right HTML element. Instead of making everything a <div>, meaningful tags let a screen reader interpret the page correctly. Here is the wrong versus the right approach:
<!-- WRONG — meaningless to a screen reader, not keyboard-accessible -->
<div class="btn" onclick="submit()">Submit</div>
<div class="title">Our Services</div>
<!-- CORRECT — semantic tags; keyboard and screen-reader friendly -->
<button type="submit">Submit</button>
<h2>Our Services</h2>
<!-- Always descriptive alt text on images -->
<img src="/team.jpg" alt="Barel Yazılım developer team in the office" /></code>A Practical Accessibility Checklist
- Descriptive alt text on all meaningful images, empty alt (alt="") on decorative ones.
- Sufficient color contrast between text and background (at least 4.5:1).
- All functionality reachable by keyboard, with a visible focus indicator.
- Form fields with <label>, error messages clear and programmatically linked.
- A meaningful heading hierarchy (single H1, ordered H2/H3); information not conveyed by color alone.
- Captions/transcripts for video and audio.
These improvements also overlap with Core Web Vitals and overall quality; we covered the technical side in our guides on what an SEO-friendly website looks like and what Core Web Vitals are.
Conclusion
Web accessibility isn’t an "extra" — it’s a core part of a quality website: it reaches a wider audience, strengthens your SEO and reduces legal risk. The good news is that most improvements come down to basic practices like semantic HTML, alt text and keyboard support. If you’d like us to assess your site’s accessibility, get in touch or request a quote.