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HTML5 outliner is a great tool that allows you check Your HTML Structure. By examining the outline of your HTML5 markup, you will get an overview of your document. Thus, you may make sure whether you have used headings and sections elements correctly.
This HTML5 tool enables you paste in your code, point it to a URL or upload a file easily. With these new elements, you are able to make your content flow in a logical manner. As a web designer or developer, the HTML5 outliner is truly another useful tool to have in your toolkit.
Moreover, there is another HTML5 outliner (h5o), which is an implementation of the algorithm in JavaScript. This tool aims to produce outlines in decent browsers and has a Google Chrome extension, which uses the HTML5 outline algorithm to create a table of contents. Try it if necessary.
