Markdown Cheat Sheet: Syntax, Tables, and Extended Features

Writing consistent, well-structured documentation requires a solid grasp of markup formatting. Markdown simplifies HTML tag creation by using plain-text characters to structure headings, tables, lists, links, and code blocks. This cheat sheet serves as a comprehensive reference guide for standard Markdown syntax, GitHub-Flavored Markdown (GFM) extensions, and common formatting solutions.

What is the Quick Reference Syntax?

This section provides quick-reference lookup tables for the most frequently used Markdown syntax elements.

Headings

Always put a single space after #. Most Markdown parsers require it; some are forgiving, but all accept it.

Text Emphasis

Lists

Always put a blank line before the first list item if it follows a paragraph block.

Links and Images

Blockquotes

Code Blocks

Horizontal Rules & Dividers

Any of these on their own line produces <hr />:

Put blank lines before and after to avoid being parsed as a heading underline.

Escaping Special Characters

Prefix any Markdown special character with a backslash \ to render it literally:

Special characters that can be escaped: \ * _ {} [] () # + - . !

How to Use Fenced Code Blocks with Language Tags?

Always specify the language after the opening fence. It enables syntax highlighting in GitHub, VS Code previews, and static site generators.

```javascript
const greet = (name) => `Hello, ${name}!`;
```

```python
def greet(name):
    return f"Hello, {name}!"
```

```bash
echo "Hello, world!"
```

```sql
SELECT name, email FROM users WHERE active = true;
```

For a diff block, lines starting with + render green and lines with - render red:

```diff
- const url = "http://example.com";
+ const url = "https://example.com";
```

To show a code fence inside a code fence, use more backticks on the outer fence:

````markdown
```js
// this renders as a code block inside the example
```
````

How to Format Tables with Mixed Alignment?

A full GFM table uses hyphens for headers and pipes to separate columns. You can customize text alignment by adding colons to the separator row.

| Name       | Role      |   Salary |
| :----------| :-------: | -------: |
| Alice      | Engineer  |   $95,000 |
| Bob        | Designer  |   $88,000 |
| Carol      | Manager   |  $110,000 |

Renders as:

What are the GitHub-Flavored Markdown (GFM) Extensions?

GFM is GitHub’s superset of CommonMark. It is widely supported by static site engines (including this site via remark-gfm).

• Task lists: Rendered as checkbox lists.
  MARKDOWN

  WrapMonokaiDraculaOne DarkNight OwlSynthWave '84NordGitHub DarkGitHub LightTokyo NightGruvbox DarkRosé PineCopyCopied!

  - [x] Write the README
  - [ ] Write tests

• Strikethrough: Wrapping text in double tildes ~~ renders as strikethrough.
• Autolinks: Bare URLs and email addresses become clickable without brackets (e.g. https://example.com).

How do I Use Footnotes in Extended Markdown?

Footnotes are supported in GitHub, Obsidian, and many static site generators.

Here is a sentence with a footnote.[^1]

[^1]: This is the footnote content. It will render at the bottom of the page.

How does Markdown Behavior Vary Across Parsers?

Different applications parse Markdown differently. Here is a feature availability breakdown:

For this site, all GFM extensions are supported, and JSX components work in .mdx files.

Summary Checklist

• Use ATX style headings (#) with a single space.
• Format emphasis with asterisks (* and **) or GFM tildes (~~).
• Build GFM tables using pipes and hyphens with colon alignment.
• Frame code blocks with triple backticks and language tags.
• Separate blocks (lists, tables, dividers) with blank lines.

Frequently Asked Questions

Can I write standard HTML tags inside Markdown?

Yes. Most Markdown parsers support inline HTML fallbacks. You can write tags like <u>underlined</u> or <img width="100"> directly in your document.

How do I write multi-line footnotes?

To span a footnote over multiple paragraphs, indent the subsequent paragraphs with four spaces or a tab under the footnote definition.

Can I combine MDX components inside GFM tables?

No. Standard markdown tables do not render JSX or MDX components inside cells reliably. Use HTML <table> syntax if you need interactive elements inside columns.

What to Read Next

• Code Blocks in Markdown: Syntax Highlighting Guide — Deep dive into inline code and syntax-highlighted blocks.
• Tables in Markdown: Create & Format Data — Detailed tutorial on aligning and formatting tabular data.
• Images in Markdown: Complete Guide — Master referencing local images, alt text, and clickable illustrations.