Heading Structure Checker
A clean H1→H6 outline is how screen readers navigate and how AI engines decide what a passage is about. Skipped levels break both.
Free · No sign-up · Reads the raw HTML a crawler sees
Skipped levels are an accessibility defect
Going from H2 straight to H4 breaks the document outline. Screen-reader users navigate by heading level — jumping levels makes the page structure unreliable in a way sighted users never notice.
This falls under WCAG 1.3.1 (Info and Relationships). It is worth stating plainly that a full accessibility assessment needs manual testing with assistive technology and expert review; heading hierarchy is one of the few parts a tool can check honestly.
The usual cause is styling. Someone needed smaller text and reached for H4. Use CSS for size and keep the level for structure.
Why AI engines care about the outline
AI answers quote passages, and they use the nearest heading to decide what a passage is about. A wall of text with no subheadings gives them nothing to anchor a citation to.
This is the most reliable structural change you can make for AI visibility: break long content into H2 sections with headings that read like the questions people ask.
How to use it
- Enter the page URL — Any public page.
- Read the outline — It should read like a table of contents.
- Fix skipped levels — Change the level, keep the styling in CSS.
Frequently asked questions
Why do skipped heading levels matter?
Screen-reader users navigate by level, so a jump from H2 to H4 misrepresents the page structure. It is a WCAG 1.3.1 issue as well as a clarity problem.
How many H2 headings should a page have?
There is no fixed number. As a rule of thumb, long-form content wants a section break every few hundred words — enough that each section has one clear subject.
Does this tool check full accessibility?
No. It checks heading hierarchy only. Real accessibility validation requires manual testing with screen readers and keyboard navigation, plus expert review.