Large DOM, too many elements: Crawl Audit check 78

Short answer: the DOM is the tree of elements your HTML builds: every div, link and span. The bigger it is, the more work the browser does each time something changes. Check 78 warns at 1,500 elements or more. It's a low-impact check, but a very large page can make taps feel slow (check 73).

What Crawl Audit checks

• Full report: Lighthouse's DOM size figure when PageSpeed provides one.
• Free check: a count of every element in the HTML, including the head.
• Pass: under 1,500. Warning: 1,500 or more.

That 1,500 line is Crawl Audit's own. Lighthouse's older DOM size audit warned at about 800 elements in the body and flagged an error at about 1,400. In Lighthouse 13 that audit became the "Optimize DOM size" insight, which "only fails if there is a large layout or style recalculation exceeding a duration of 40ms."

What Google says

• Lighthouse: "A large DOM tree in combination with complicated style rules can severely slow down rendering and interactivity."
• web.dev: "Expensive layout work can affect a page's Interaction to Next Paint (INP)".

On devmarde.com

Our homepage had about 2,000 elements on 3 October, so it gets this warning. It's a long page, and PageSpeed listed the DOM size insight for it too. Its TBT was 30ms (check 76), so it isn't holding taps up much yet.

How to trim it

• Remove wrapper elements that only exist for styling, such as nested divs from page builders.
• Don't render long lists, menus or carousels in full when only part is visible. Paginate or load more on demand.
• Avoid hidden copies of content (one menu for mobile, one for desktop) where a single version will do.

Sources

• Chrome for Developers, Avoid an excessive DOM size and Optimize DOM size insight (8 October 2025), checked 3 October 2026.
• web.dev, How large DOM sizes affect interactivity.