making h1 tag width code example

Example 1: html h1 size

h1  =>    32px    (2em)
h2  =>    24px  (1.5em)
h3  =>  20.8px  (1.3em)
h4  =>    16px    (1em)
h5  =>  12.8px  (0.8em)
h6  =>  11.2px  (0.7em)

Example 2: how tomake a h1 tag

<h1>Hello World</>