The quick answer: Wrap text in double equals signs —
==highlighted text== — to apply a yellow highlight background.
Syntax
This is ==highlighted== text.This renders with a yellow/amber background on the highlighted words — the same visual effect as a physical highlighter pen.
Platform Support
Highlight is an extended markdown feature, not part of CommonMark. Support varies:
- Obsidian — full native support ✅
- Typora — supported (enable in preferences) ✅
- GitHub — not supported ❌
- Discord, Slack, Notion — not supported ❌
Fallback for GitHub: HTML mark tag
On platforms that don't support ==highlight==, use the HTML tag:
This is highlighted text.
GitHub renders the element with a yellow background. This is your best cross-platform option.
When to Use Highlighting
- Mark the single key takeaway in a paragraph
- Draw attention to important terms in technical documentation
- Annotate study notes (Obsidian is perfect for this)
- Review and feedback workflows — highlight sections needing revision
Don't Overuse It
Like bold text, highlighting loses its impact when overused. Highlight no more than one or two phrases per section — the visual contrast only works when most text is unhighlighted.
Full reference: Markdown Highlight.