Markdown Cheatsheet Cheat Sheet

Complete Markdown reference — basic syntax, extended GFM features, tables, code blocks, admonitions, footnotes, and advanced formatting for documentation and READ.

Last Updated: May 1, 2025

Basic Syntax

Element	Syntax	Output
Heading	# H1, ## H2, ### H3...###### H6	6 levels of headings
Bold	bold or __bold__	bold
Italic	italic or _italic_	italic
Strikethrough	~~strikethrough~~	Crossed out
Link	[text](https://url)	Clickable link
Image	![alt](image.png)	Embedded image
Code Inline	`code`	Monospace inline
Blockquote	> quoted text	Indented quote

Lists & Code Blocks

- item
- item2

Unordered list with dashes, asterisks, or plus signs

1. First
2. Second

Ordered list — numbers auto-increment (all 1s works too!)

- Nested item

Indent 2 spaces to nest lists

```python
code here
```

Fenced code block with language for syntax highlighting

indented 4 spaces

Indented code block (no language support)

```mermaid
graph TD;
A-->B;
```

Mermaid diagrams in GitHub/GitLab

Tables & Advanced (GFM)

| Col1 | Col2 |
|------|------|
| A | B |

Basic table — colons in separator align: :--- left, ---: right, :---: center

| Left | Center | Right |
|:-----|:------:|------:|
| L | C | R |

Left, center, right alignment

- [ ] unchecked
- [x] checked

Task lists (checkboxes in GitHub issues/PRs)

~~strikethrough~~

Strikethrough text (GFM extension)

footnote[^1]
[^1]: The footnote text.

Footnotes (some renderers)

--- or *** or ___

Horizontal rule (3+ characters)

[^1]: Footnote definition

Footnote reference and definition

GitHub-Flavored Special Features

Item	Description
`Mention`	@username notifies a user
`Issue Reference`	#123 links to issue/PR #123 in the repo
`Emoji`	:smile: → 😄. Full list at emoji-cheat-sheet.com
`Collapsible Sections`	Click Hidden content
`Diff Syntax`	```diff - removed + added ``` — colored diff in code blocks
`Alerts/Admonitions (GH)`	> [!NOTE] / > [!WARNING] / > [!IMPORTANT] / > [!TIP] / > [!CAUTION]

Pro Tip: Use the Markdown All in One VS Code extension for keyboard shortcuts (Ctrl+B bold, Ctrl+I italic) and automatic table of contents generation. Preview with Ctrl+Shift+V.