Enter a URL to see its H1-H6 outline as a visual hierarchy, and run real checks for common heading structure mistakes.
Headings (<h1> through <h6>) form a document outline that both search engines and assistive technology like screen readers rely on to understand a page's structure. This tool extracts every heading from a page in document order, renders it as an indented outline so the hierarchy is easy to see at a glance, and runs a handful of concrete checks: exactly one H1, no skipped levels, and headings that otherwise nest in a sensible order.
Tip: a skipped level (like jumping from H2 straight to H4) isn't always visually obvious on the page, but it can confuse screen reader users who navigate by heading level.
The H1 is conventionally treated as the single main topic of the page, both by search engines building an understanding of the content and by screen reader users who often jump straight to it to orient themselves. Zero H1s leaves the page without a clear topic anchor; multiple H1s can dilute or confuse that signal.
Screen reader users frequently navigate a page by jumping between headings of a given level. Skipping from H2 straight to H4 without an H3 breaks that expected nesting and can make the page's structure harder to follow non-visually, even though sighted users may not notice anything.
Search engines use headings to understand page structure and topic hierarchy, which can indirectly help relevance matching, but a clean heading structure is primarily an accessibility and usability best practice rather than a guaranteed ranking boost.
It can technically render fine, but it's considered a missed opportunity and a minor accessibility gap in almost all cases — nearly every page benefits from a single, clear H1 describing what the page is about.