Markdown Bold and Italic to HTML Strong and Em Tags

Bold and Italic Emphasis in Markdown

Markdown uses asterisks (*) and underscores (_) to indicate emphasis, which converts to HTML <em> (italic) and <strong> (bold) tags.

Italic Text

Wrap text in a single asterisk or underscore for italic emphasis:

*italic with asterisks*
_italic with underscores_

Converts to:

<em>italic with asterisks</em>
<em>italic with underscores</em>

Bold Text

Wrap text in double asterisks or underscores for bold emphasis:

**bold with asterisks**
__bold with underscores__

Converts to:

<strong>bold with asterisks</strong>
<strong>bold with underscores</strong>

Combined Bold and Italic

Use triple asterisks or underscores for text that is both bold and italic:

***bold and italic***
___bold and italic___

Converts to:

<strong><em>bold and italic</em></strong>

Nesting Emphasis

You can nest bold inside italic or vice versa:

*This is italic and **this is bold** inside it*

Produces:

<em>This is italic and <strong>this is bold</strong> inside it</em>

Asterisks vs. Underscores

While both work, asterisks are preferred in most style guides because underscores can cause issues mid-word. For example, un_frigging_believable may not render as expected with some parsers, while un*frigging*believable works consistently.