The Heading Tag Checker reads the HTML you paste and lists every H1 to H6 heading in the order it appears, as an indented outline. It warns about a missing or repeated H1, skipped levels (such as H2 straight to H4) and empty headings, so you can fix the structure that both search engines and screen readers rely on.
Made for marketers and seo. Typical uses:
The sample page has an H1 "Guide to SEO", H2 "Basics", H3 "Keywords", H2 "Advanced", H4 "Schema" and an empty H2. The checker reports two problems: a skipped level (an H2 followed by an H4) and an empty H2. Making "Schema" an H3 and filling in or removing the last heading fixes both.
It reads the HTML you paste, so headings added by JavaScript after the page loads are not seen unless you paste the rendered HTML (from the browser inspector). It does not fetch live URLs.
Accuracy: Results show what the tool can measure at the moment you run it and can differ from what search engines see. Use them as guidance.
Expert Tip
Read only your headings, top to bottom: they should work like a table of contents. If a heading does not describe the text beneath it, rewrite it.
Headings, the h1 to h6 tags, give a page its outline. Search engines use them to understand the topic and its parts, and screen readers let people jump from heading to heading. The Heading Tag Checker reads the HTML you paste, lists every heading in page order as an indented outline, and flags problems. To use it, open the page, view its source (Ctrl+U) and copy the code, paste it into the box and press Analyze headings. The "Try an example" link loads a sample.
The checker tests for these problems.
The sample page has the outline: H1 "Guide to SEO", H2 "Basics", H3 "Keywords", H2 "Advanced", H4 "Schema" and an empty H2. The checker reports two problems. First, a skipped level: an H2 is followed by an H4, "Schema". Second, the sixth heading is an empty H2. The fix is to make "Schema" an H3 under "Advanced" and give the last heading some text or remove it. The indented outline makes the structure visible at a glance.
Use one H1 that says what the page is about, H2s for the main sections and H3s for the parts of those sections, and do not choose a heading level for its size. Style the text with CSS instead. Make each heading describe the text that follows, include the topic words naturally, and keep them short. Do not use a heading for a tagline, a button or a navigation label. A good outline reads like a table of contents, and you can test that by reading only the headings.
The checker reads only the HTML you paste, so headings that are added by JavaScript after the page loads are not seen unless you copy the rendered HTML from the browser's inspector. It does not fetch addresses, check the whole site, or look at headings made with other markup such as styled paragraphs. Page content stays in your browser. To check the words in your headings and body text, use the Keyword Density Checker, and the Readability Checker scores the text under them.
Headings are one part of on-page SEO. The Alt Text Checker tests images, the Canonical Tag Checker tests duplicate-content signals, and the SEO Score Checker gives an overview. The Slug Generator helps you name the page's address to match its main heading.
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