Check page headings, with the HTML Headings tool.
Headings are used to structure the textual content of a web page and are an important on-page SEO factor. The most important heading is the H1 heading followed by the H2 and H3. There are six levels of headings available from H1 to H6.
The H1 heading should contain the main subject of a page. Use only one H1 on a web page.SEO Content Tools, SEO Tools