Wrap the text in two asterisks or two underscores. Both give the same bold text, but only asterisks work in the middle of a word, so most style guides pick asterisks and use them everywhere.
All ways to write it
Two asterisks on each side. Works everywhere, including inside a word.Works everywhere**bold text**
Two underscores. Same result, but not inside a word.Works everywhere__bold text__
Three asterisks for bold and italic together.Works everywhere***bold italic***
Example
You type
Deploys run **every weekday at 09:00 UTC**.
Use the **Pro**fessional plan for **bold *and* italic** in one phrase.You get
Deploys run every weekday at 09:00 UTC.
Use the Professional plan for bold and italic in one phrase.
Questions
Should I use asterisks or underscores for bold?
Asterisks. They work in every position, while underscores inside a word (like snake__case__name) are left as plain text by CommonMark and GitHub.
Why is my bold text not working?
The most common cause is a space just inside the markers: ** bold ** is not bold. The markers must touch the text: **bold**.
How do I show literal asterisks?
Escape them with a backslash: \*\*not bold\*\* prints the asterisks as typed.
Bold in Confluence
Inside a Markdown Macro+ macro, **bold** renders as bold text in the live preview and on the saved page. When you import .md files with Markdown Importer, bold becomes normal Confluence bold formatting.