What Makes a Good Website

Why W3C Valid Code Is a Non-Negotiable (Even If No One's Talking About It)

No one ever lost sleep over invalid HTML.

But maybe they should’ve.

Let me tell you what happened:

A client of mine once asked why his brand-new dealership website wasn’t ranking in Google. He was paying thousands a month in SEO. Great content, solid backlinks…

But still buried on page 6.

I ran a W3C validator. Over 230 errors.

Unclosed tags, duplicate IDs, missing alt attributes, improperly nested elements—you name it.

And these weren’t harmless. They were breaking Googlebot. Sections weren’t being indexed. Links weren’t crawlable. Meta tags were being ignored.

All because the code was a mess.

If you are a coder and someone asks you what constitutes good code then you have to say the quality of the code.

The way you establish the quality of the code is that it meets all the standards and doesn’t have any errors. The way you find errors is by validating the code and if you can’t validate the code how can the developer be sure they didn’t forget to close a tag?

Professionals write code that meets all the standards and validates so a good website does the same.

The Benefits of W3C Validation

• Improved Accessibility:
• Improved Search Engine Optimization:
• Improved Cross-Browser Compatibility:
• Improved User Experience:

The (RNIB) found that 97% of websites fail to meet the basic accessibility guidelines set by the W3C.

Valid code helps to make sure that code is consistent, readable, and accessible to all users.

Here's what most people miss:

W3C valid code isn’t about being a code snob, it’s about creating a site search engines (and screen readers) can actually use.

Let’s break it down:

• Googlebot relies on well-formed code to parse and index your content.
• Screen readers rely on semantic HTML to give disabled users a real experience.
• Crawl efficiency depends on clean markup and logical structure.

And here’s the kicker:

Broken code = broken UX = broken SEO = broken business.

W3C validation touches everything:

• ADA compliance
• Core Web Vitals
• Crawl Budget
• Page rendering
• Mobile usability

So when developers say, “Oh that doesn’t matter…” Run.

Because your rankings, traffic, and reputation depend on it.

Real talk:

I’ve seen dealerships go from 100+ W3C errors to a clean pass and I've seen their rankings climb because of it, without adding a single new backlink.

Why? Because clean code lets Google do its job. Because clean code makes your site accessible. Because clean code is easier to maintain, easier to improve, and harder to break.

You want a site that loads fast, ranks high, converts better, and doesn’t break every time a plugin updates?

Start with valid code.

Everything else is built on top of that.