How to Italicize Text in Markdown
To italicize text in Markdown, wrap it in single asterisks: *italic text*. A single underscore on each side (_italic text_) works too. Both produce an <em> element, and the choice is mostly style — though asterisks behave better inside words.
Platform Support
Italics signal emphasis, titles of works, foreign phrases, or terms being defined. Like bold, the markers must hug the text: *italic* works, * italic * does not. The parser requires a non-space character immediately after the opening marker and immediately before the closing one.
The asterisk-versus-underscore question matters more for italics than for bold because single underscores collide with real-world text more often. Variable names like user_name_field contain underscores that you do not want interpreted as emphasis — and CommonMark protects you here by ignoring underscores that are flanked by letters or numbers. The flip side is that you cannot use underscores for mid-word emphasis: un_believ_able stays literal, while un*believ*able italicizes the middle of the word.
A subtle gotcha appears when italics sit next to punctuation or other markers. Nesting bold and italic with the same character can confuse parsers: ***text*** is well-defined (bold + italic), but **bold with *italic* inside** is clearer when you mix characters, e.g. **bold with _italic_ inside**. Using asterisks for one level and underscores for the other removes any ambiguity about which marker closes which span.
If you write a lot of math or filenames, remember the backslash escape: \*literal asterisk\* and \_literal underscore\_ keep the characters visible. This is especially useful in documentation that shows glob patterns like *.md, which would otherwise start an italic span that silently swallows your asterisk.
Examples
*italic text*
_also italic_italic text
also italic
Make text italic using single asterisks or underscores.
*italic text*italic text
_italic text_italic text
***bold and italic***
___also bold and italic___bold and italic
also bold and italic
Combine bold and italic using triple asterisks or underscores.
un*believ*ableunbelievable
Mid-word italics require asterisks; underscores between letters stay literal.
**bold with _italic_ inside**bold with italic inside
Using different characters for each level keeps the nesting unambiguous.
Common Mistakes
* italic text **italic text*Spaces directly inside the markers prevent the parser from recognizing the emphasis span.
un_believ_ableun*believ*ableUnderscores surrounded by letters are intentionally ignored (to protect snake_case identifiers). Use asterisks for emphasis inside a word.
*italic***italic*Unbalanced markers leave stray asterisks in the rendered output. Open and close with the same number of characters.
Platform Notes
GitHub
Both *text* and _text_ render as italics everywhere on GitHub. The underscore form is common in prose-heavy docs.
Discord
Both *text* and _text_ work for italics in Discord messages.
Slack
Slack uses _single underscores_ for italics. Asterisks make text bold in Slack, so *text* will not italicize there.
Notion
Typing *text* or _text_ followed by a space auto-converts to italics. Notion then stores it as rich text rather than Markdown.
Frequently Asked Questions
How do I italicize text in Markdown?
Wrap the text in single asterisks (*italic*) or single underscores (_italic_). Both render as an <em> element in HTML.
Should I use asterisks or underscores for italics?
Either works for whole words, but asterisks are more reliable: they work mid-word and avoid conflicts with snake_case identifiers. Many style guides standardize on asterisks for emphasis.
Why does _text_ not work inside a word?
CommonMark deliberately ignores underscores flanked by letters or numbers so that identifiers like user_id are not mangled. Use asterisks (un*believ*able) for intra-word emphasis.
How do I combine italic with bold?
Triple asterisks (***text***) make text bold and italic. For partial overlap, mix markers for clarity: **bold with _italic_ inside**.
Related Syntax
Bold
Learn how to make text bold in Markdown using double asterisks or underscores.
Strikethrough
Learn how to strike through text in Markdown using double tildes (~~text~~).
Blockquotes
Learn how to create blockquotes in Markdown with the > character, including multi-paragraph quotes, nested quotes, callouts/admonitions, and lazy continuation rules.