Markdown Syntax Reference
Complete guide to Markdown formatting. Works everywhere: GitHub, GitLab, Notion, Obsidian, Jekyll, and any plain-text editor. Fast, universal, and readable.
Headers & Formatting
Headers
Use # for headers. More hashes = smaller heading (levels 1-6).
# Heading 1
## Heading 2
### Heading 3
Bold & Italic
Double asterisks or underscores for bold. Single for italic. Combine for both.
**bold text** or __bold text__
*italic text* or _italic text_
***bold and italic***
Code
Use single backticks for inline code. Triple backticks for code blocks with optional syntax highlighting.
`inline code`
```javascript
function hello() {
console.log("Hello");
}
```
Links & Images
Links
Square brackets for text, parentheses for URL. Optional title in quotes.
[Link text](https://example.com)
[Link with title](https://example.com "Title")
Images
Same as links but with an exclamation mark prefix. Alt text is required.
Lists & Tables
Lists
Unordered lists use -, *, or +. Ordered lists use numbers. Indent for nesting.
- Unordered item
- Another item
- Nested item
1. First ordered item
2. Second ordered item
- [ ] Task list item
- [x] Completed task
Tables
Use pipes and hyphens to create tables. Colons control alignment.
| Left | Center | Right |
|:-----|:------:|------:|
| Text | Text | Text |
Blockquotes & Horizontal Rules
Use > for quotes. Three hyphens, asterisks, or underscores for horizontal rules.
> This is a blockquote
> Multiple lines supported
---
Horizontal rule above
Extended Syntax
These features are supported by GitHub Flavored Markdown and most modern parsers:
Strikethrough: ~~deleted text~~
Footnotes:
Here's a sentence with a footnote.[^1]
[^1]: This is the footnote content.
Automatic URL linking: URLs in plain text become clickable
Escape characters: Use backslash \ to display literal Markdown characters: \*not italic\*
Why Markdown?
Markdown is the universal standard for plain-text formatting. It's readable as-is, converts cleanly to HTML, and works everywhere. No proprietary formats, no lock-in, no bloat.
Where it's used:
- GitHub README files, issues, and pull requests
- Documentation sites (Jekyll, Hugo, MkDocs)
- Note-taking apps (Obsidian, Notion, Bear)
- Blogging platforms (Ghost, WordPress with plugins)
- Messaging apps (Discord, Slack, Reddit)
Learning Markdown is a one-time investment that pays off across dozens of platforms. It's fast to write, fast to read, and impossible to obsolete.