🚨 Source code vs rendered HTML: Critical Differences you must know


Critical knowledge alert 🚨🚨🚨

As a technical SEO, it’s crucial you know the difference between source code and rendered HTML them.

Source code

It is the initial code of the page before any JavaScript files are executed and CSS files are parsed.

It’s the code you see when viewing the source code of a page in your browser.

Rendered HTML

It is displayed after CSS and JavaScript are processed.

When you inspect an element on a page using Chrome dev tools, you’re looking at the rendered HTML.

Why is it important for SEO?

JavaScript can significantly change a page's contents AND all SEO elements, for example:

  • Rewrite the title tag
  • Add a noindex tag
  • Remove a canonical

Now, here’s the thing:

Google uses the rendered HTML of your page to evaluate this page’s optimization.

It means that if you’re only relying on the source code for your SEO efforts, it’s easy to miss many important things.

In the next newsletter next Wednesday, I'll show you the tools that will help you see the rendered HTML of the page.

🚀 Psst... Ready to master JavaScript SEO and other aspects of technical SEO?

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I poured 13 years of technical SEO experience + 500 hours into creating this course so that you could save your time and become a real pro.

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Source code vs rendered HTML: Critical Differences you must know

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