Markdown Cheat Sheet

Headings

# Heading 1
## Heading 2
### Heading 3
#### Heading 4
##### Heading 5
###### Heading 6

Always put a space after the #. Most Markdown processors require it.

Alternative syntax for H1 and H2:

Heading 1
=========

Heading 2
---------

Text Formatting

**Bold text**
*Italic text*
***Bold and italic***
~~Strikethrough~~

You can also use underscores: _italic_ and __bold__. Asterisks are more common and work in more contexts (mid-word emphasis).

Links

[Link text](https://example.com)
[Link with title](https://example.com "Hover text")
<https://example.com>

Reference-style links for cleaner source:

[Link text][ref]

[ref]: https://example.com "Optional title"

Images

![Alt text](image.png)
![Alt text](image.png "Optional title")

To resize images, you need HTML:

<img src="image.png" alt="Alt text" width="400">

Lists

Unordered:

- Item one
- Item two
  - Nested item
  - Another nested
- Item three

Ordered:

1. First
2. Second
3. Third

Ordered lists auto-number — you can use 1. for every item and the renderer will count correctly.

Task lists (GitHub Flavored):

- [x] Done
- [ ] Not done
- [ ] Also not done

Blockquotes

> This is a blockquote.
>
> It can span multiple lines.
>
> > Nested blockquotes work too.

Code

Inline code:

Use `backticks` for inline code.

Code blocks with syntax highlighting:

```javascript
function greet(name) {
    return `Hello, ${name}!`;
}
```

Common language identifiers: javascript, python, bash, json, html, css, swift, go, rust, sql, yaml, markdown.

Code block without highlighting:

```
Plain code block
No highlighting
```

Tables

| Header 1 | Header 2 | Header 3 |
|----------|----------|----------|
| Cell 1   | Cell 2   | Cell 3   |
| Cell 4   | Cell 5   | Cell 6   |

Alignment:

| Left     | Center   | Right    |
|:---------|:--------:|---------:|
| text     | text     | 123      |

For a deep dive, see our full guide: Markdown Table Syntax.

Horizontal Rules

---
***
___

All three produce a horizontal line. Use --- — it’s the most common convention.

Line Breaks

End a line with two spaces to create a line break (soft return):

First line
Second line (same paragraph)

Or use a blank line for a new paragraph:

First paragraph.

Second paragraph.

Escaping Characters

Use a backslash to display literal Markdown characters:

\* Not italic \*
\# Not a heading
\[Not a link\]
\| Not a table pipe

Characters you can escape: \ ` * _ {} [] () # + - . ! |

GitHub Flavored Markdown (GFM) Extras

These features are supported by GitHub, GitLab, and most modern Markdown apps:

Autolinked URLs:

https://example.com

Renders as a clickable link without bracket syntax.

Footnotes:

Here is a statement[^1].

[^1]: This is the footnote text.

Emoji (GitHub):

:thumbsup: :rocket: :warning:

Alerts (GitHub, new):

> [!NOTE]
> Useful information.

> [!WARNING]
> Important warning.

Extended Syntax

Some Markdown renderers support additional features beyond GFM:

Mermaid diagrams:

```mermaid
graph TD
    A[Start] --> B{Decision}
    B -->|Yes| C[Do thing]
    B -->|No| D[Don't]
```

Supported by GitHub, GitLab, Obsidian, and MDViewer.

Math (KaTeX/LaTeX):

Inline: $E = mc^2$

Display:
$$
\sum_{i=1}^{n} x_i = x_1 + x_2 + \cdots + x_n
$$

Supported by GitHub, Obsidian, Jupyter, and MDViewer.

Definition lists:

Term
: Definition text

Supported by some processors (PHP Markdown Extra, Pandoc). Not standard GFM.

Quick Reference Table

Previewing Your Markdown

Writing Markdown is easy. Seeing how it renders without pushing to GitHub or opening a heavy editor — that’s where a dedicated viewer helps.

MDViewer is a native macOS app that renders GitHub Flavored Markdown including tables, code blocks with syntax highlighting, Mermaid diagrams, and KaTeX math. Double-click any .md file in Finder to see it rendered instantly. Currently free for early adopters.

You can also use our free online Markdown viewer at getmd.ma/viewer — drop a file in your browser, no install needed.

Try MDViewer

MDViewer is currently free for early adopters — all features included. Download it and see if it fits your workflow.

Requires macOS 13.0 or later. Intel and Apple Silicon.