Why look at a page without JavaScript?
Many pages are only partly in the code the server sends. The rest is added by JavaScript after the page opens: sometimes a menu or a gallery, sometimes all of the text. Whoever reads the page without running its scripts gets only the first part.
Few visitors switch JavaScript off, but they are not the only readers. Google does run scripts, though it does so in a second step that can come later than the first reading of the code. Many other crawlers, including a number of those that collect pages for AI assistants and for link previews in messengers, don’t run scripts at all. A script can also fail to load on a poor connection. In all these cases, what counts is what the code already holds.
How this test works
Our server downloads your page and reads its code. It never runs scripts, so what it sees is what a reader without JavaScript receives. It then checks, one by one, the things such a reader needs: a title, a description, a main heading, text, links that lead somewhere, images that have a source.
It also reads the page’s noscript tags. These hold what a page offers when scripts don’t run: a fallback image, a message, or often just a tracking pixel.
JavaScript disabled and enabled
To show what scripts add, the report sets two results side by side. For the first, JavaScript disabled, we read the code ourselves. For the second, JavaScript enabled, we ask Google’s PageSpeed Insights to load the same page in Chrome and run every script. The table compares the two: how many elements the page has before and after, whether the title and description are there, how many images and scripts are loaded, and how many links can’t be followed.
Under the table the page is shown both ways. On the left is the page without JavaScript: its own code, drawn by your browser in a frame where scripts are not allowed to run, at the width of a phone. On the right is a screenshot from Google’s test, with scripts run. A blank or broken left side next to a complete right side is a page that depends on JavaScript.
For the first half we download the code three times, because a page doesn’t always answer the same way twice, and read the copy of middle size. If the copies differ noticeably, the report says so. For the second half Google loads the page in Chrome once.
The second half takes most of the time, up to a minute. If Google’s service doesn’t answer, the report is shown with the first half only and says so.
What is a good result?
There is no official score for this, so the report gives a sign, not a number. A tick means the page’s content is in its code and nothing needs attention. An exclamation mark means part of it depends on JavaScript, such as images that load only through a script or links that aren’t real links. A cross means the page is close to empty without JavaScript, or is hidden until a script shows it.
The one fixed mark is Seokla’s own: a page with fewer than 50 words in its code, and scripts on it, is treated as built in the browser.
What this test can’t tell you
The two halves come from different places. JavaScript disabled is our own reading of the code. JavaScript enabled is Google’s test in Chrome on an emulated phone. They count the same things where they can, such as elements, but not everything can be matched: Google’s test doesn’t report the number of words, so text is shown for the disabled half only.
The two views are made differently as well. The one with JavaScript is a picture taken by Google. The one without is a live copy drawn by your own browser from the page’s code: it loads the page’s styles and images from the site itself, so it needs a moment, and a font or an image that the site doesn’t share with other sites may be missing. Treat it as a close likeness, not an exact picture. Pages over 1.5 MB are not drawn.
A site that sends phones different code from computers will show differences that have nothing to do with JavaScript. To see the page exactly as Google renders it for search, use the URL Inspection tool in Google Search Console.
We read the code, not the screen. Text that is in the code but hidden by a stylesheet until a script reveals it counts as present here, except where the page hides its whole body with an inline style, which we do check. A page can also work without JavaScript and still be awkward to use; this test doesn’t judge that.