What a crawler actually receives
When you open a page in a browser, the browser downloads the HTML, runs the JavaScript and draws the result. Many modern sites send almost empty HTML, such as one empty container and a script, and let JavaScript build the page. A person sees a full page. A crawler that does not run the script receives the empty container.
Google can render JavaScript, though in a second, slower pass. Many AI crawlers do not run scripts, and their operators say little about it, so the safe assumption is that the HTML you send is all they read.
What we found in our own sites
On 31 October 2026 we fetched the raw HTML of ten sites we had built and counted the readable text, with no JavaScript.
| Group | Sites | Readable text in the raw HTML |
|---|---|---|
| Complete HTML first | 7 | 4,946 to 19,225 characters, one H1 and structured data |
| Filled in by JavaScript | 3 | 27 to 50 characters, no H1, no structured data |
The three were fast to build and look good in a browser. To a crawler without JavaScript they are close to blank. We are fixing them, and we did it to our own work first so we could say so.
How to check yours in a minute
- Open your page, right-click and choose View page source (not Inspect). This is the HTML a crawler receives.
- Look for your main heading and a few sentences of your real text. If you only see an empty container and script tags, the page depends on JavaScript.
- Or paste your address into our free website check, which fetches the page the way a crawler does and lists what it finds.
How to fix it
- Build static-first. Generate complete HTML for every page, then add scripts for interaction. This is how this site is built.
- Render on the server. A server-rendering framework sends the finished HTML for each request.
- Pre-render an existing site. If a rebuild is not possible, a build step can save the rendered HTML of each page so the text is present in the file.
What to check afterwards
A title and description on every page, exactly one H1, structured data that matches the visible content, a sitemap, and a robots file that allows the crawlers you want. Then keep an eye on Search Console and Bing Webmaster Tools. Nobody can promise that a readable site will be ranked or quoted, but an unreadable site cannot be.
