HTML – Heading elements h1, h2, h3, h4, h5 and h6
The W3C HTML5 specification describes six HTML heading elements: h1, h2, h3, h4, h5 and h6.
The height of a heading element is specified in the browser’s default stylesheet. See col 4 below.
The height of 1 em is usually 16 pixels.
The em is a unit of measure from the field of printed type, and is equal to the width of the letter M.
| HTML element | rank | example text | default stylesheet | pixel height |
|---|---|---|---|---|
| <h1> </h1> | 1 |
h1 |
font-size: 2em font-weight: bolder |
32 px |
| <h2> </h2> | 2 |
h2 |
font-size: 1.5em font-weight: bolder |
24 px |
| <h3> </h3> | 3 |
h3 |
font-size: 1.17em font-weight: bolder |
18.72 px |
| <h4> </h4> | 4 |
h4 |
font-size: 1em font-weight: bolder |
16 px |
| <h5> </h5> | 5 |
h5 |
font-size: .83em font-weight: bolder |
13.28 px |
| <h6> </h6> | 6 |
h6 |
font-size: .67em font-weight: bolder |
10.72 px |