`–`

` tags, and catch the structural problems that break navigation. Runs entirely in your browser. ### How it works The pasted HTML is parsed locally with `DOMParser` and every heading is read in document order to reconstruct the outline assistive technology announces. Three common failures are flagged: **no `

`**, **more than one `

`**, and **skipped levels** (for example an `

` jumping straight to an `

`), which breaks the logical reading order. A clean, properly nested outline is reported as passing. --- *Source: [ocxly.com/heading-structure-analyzer.html](https://ocxly.com/heading-structure-analyzer.html) — OCXLY, free 100% client-side privacy-first tools. Free heading structure analyzer — visualise your h1–h6 outline and flag missing, duplicate or skipped heading levels, entirely in your browser.*