Check out example codes for "css h sizes". It will help you in understanding the concepts better.

Code Example 1

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)

Code Example 2

<h1> Example Test </h1>

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