Heading Hierarchy Validator — Free, No Upload, Browser-Based

Paste HTML or Markdown and instantly see a visual outline of your h1–h6 heading hierarchy, with plain-English issue reports for skipped levels and multiple h1 tags. Good heading structure matters for both screen-reader accessibility and SEO — this tool catches the most common mistakes before they ship. Everything runs in your browser: no upload, no account, and your markup is never sent anywhere.

如何使用此工具

1. 選擇 HTML 或 Markdown 作為輸入格式，然後將您的內容貼入文字區域。
2. 工具會解析所有 h1–h6 標題，並檢查是否有跳級或多個 h1 標籤。
3. 在發布前檢視視覺化大綱並修正來源中任何被標記的問題。