==highlighted text== — for a yellow background highlight. For platforms that don't support this syntax (like GitHub), use the HTML Syntax
This is ==highlighted== text.This renders with an amber/yellow background behind the highlighted words — visually similar to drawing over text with a physical highlighter pen.
You can highlight a single word, a phrase, or multiple words:
The ==most important insight== is that highlighted text stands out.
Platform Support at a Glance
| Platform | ==syntax== | tag |
| --- | --- | --- |
| Obsidian | ✅ | ✅ |
| Typora | ✅ (enable in preferences) | ✅ |
| GitHub | ❌ | ✅ |
| GitLab | ❌ | ✅ |
| Notion | ❌ | ❌ |
| Discord | ❌ | ❌ |
| Slack | ❌ | ❌ |
Summary: Use ==equals== for Obsidian-only documents. Use for anything targeting GitHub. For maximum portability, use everywhere.
The HTML mark Tag (Cross-Platform Fallback)
The HTML element is the semantic standard for highlighted text:
This is highlighted text.
This is your best option for cross-platform markdown because:
- GitHub renders
with a yellow background - GitLab renders
correctly - Most static site generators respect the
element - Screen readers announce
content as highlighted
Obsidian-Specific Behavior
Obsidian has native support for the ==double equals== syntax. It renders with an amber background in both the live preview editor and the reading view.
Obsidian also supports the tag. If you want your notes to be portable (and readable on GitHub or other renderers), prefer even in Obsidian.
Obsidian custom highlight colors: With CSS snippets, Obsidian lets you add custom highlight colors using styled elements. This is useful for color-coded annotations in research notes.
Typora Behavior
Typora supports ==highlight== but it must be enabled in Preferences → Markdown → Highlight. It's off by default. Once enabled, it renders with an amber background.
GitHub Behavior
GitHub does not support ==double equals== syntax — it renders as literal equals signs. However, GitHub does render the HTML element with a yellow-tinted background.
For GitHub README files and documentation, always use for highlights.
When to Use Highlighting
Highlighting is the most visually aggressive inline formatting. Use it sparingly:
Best uses:
- The single key takeaway in a paragraph — the one thing readers must retain
- Critical warnings that bold doesn't emphasize enough
- Study notes — annotating the most important fact in a source
- Review workflows — marking sections that need revision or attention
- First occurrence of a key term in technical documentation
Avoid:
- Highlighting multiple things per paragraph
- Using highlight where bold would suffice
- Highlighting entire sentences (defeats the purpose)
Highlighting vs Bold: Which to Use When
| Formatting | Visual weight | Best for | | --- | --- | --- | | Bold | High | Key terms, action items, warnings | | Italic | Medium | Titles, technical terms, soft emphasis | | Highlight | Extreme | The single most critical fact per section | | Bold + Highlight | Maximum | Reserved for critical safety warnings |
Use highlighting even more sparingly than bold. A page with ten bolded phrases is readable. A page with ten highlighted phrases looks like a student's first attempt at note-taking.
Combining Highlight with Other Formatting
Highlighting works with other inline formatting:
==bold and highlighted== — bold + highlight
==italic and highlighted== — italic + highlight (Obsidian)
bold and highlighted — cross-platform equivalent
Highlighting in Lists and Tables
Both syntaxes work in list items and table cells:
- Normal item
- ==Critical item== that needs attention
| Feature | Notes |
| --- | --- |
| Core feature | Required for v1 |
Real-World Use Cases
Research and Study Notes in Obsidian
The classic Obsidian use case: you paste a long article or research paper, read through it, and highlight the three most important sentences. When you review later, the highlights jump out immediately without re-reading everything.
Code Review Comments on GitHub
In GitHub PR review comments, you can't directly highlight the code you're commenting on in the markdown itself. But in your review body text, using helps draw attention to the specific aspect you're addressing.
AI-Generated Content Review
When ChatGPT or Claude generates a long report, paste it into Obsidian or a markdown editor and use ==highlights== to mark the sections you've verified vs the sections that still need fact-checking. Export the final (clean, no-highlights) version through MarkdownTools.
Accessibility Consideration
Highlighting conveys information through color alone. For accessible documents, don't rely on highlight as the only indicator — pair it with text: "Critical: ==This step cannot be undone.==" instead of just ==This step cannot be undone.==
The HTML element has better accessibility support than ==equals== — screen readers specifically call out content in some configurations.
Full reference: Markdown Highlight.
Ready to put this into practice? Paste your markdown into the free MarkdownTools PDF exporter or HTML converter — no signup required.