Heading Structure Checker

📖 About this tool

Heading tags form the outline of a page: they help readers scan and tell search engines how the content is organised. After pasting HTML source, this tool extracts every h1 to h6, builds an indented outline in document order and counts each level, while checking five common problems: empty headings, headings over 60 characters, skipped levels (an H2 jumping straight to H4, for example), a missing H1, and duplicate H1s. A page should normally carry a single H1 as its main title with the rest stepping down one level at a time. The outline can be copied as indented text for pasting into a document or sharing with colleagues. The source is parsed only on your own machine. Typical uses include checking structure before publishing a long article, getting a quick picture of how an unfamiliar page is organised, and tracking down topic dilution caused by multiple H1s.

✨ Features

• Full outline extraction：Every h1–h6 listed in document order, with indentation showing the hierarchy
• Five problem checks：Empty, overlong, skipped levels, missing H1 and duplicate H1s all checked
• Counts per level：Separate H1–H6 counts plus a total, so the distribution is clear
• Precise locations：A skipped level names exactly which level jumps to which
• One-click outline copy：Copy the indented outline into a document or collaboration tool

🚀 How to use

1. Paste the page HTML source;
2. Click Check outline;
3. Review the outline and issue list;
4. Adjust the heading structure as advised.