• The Ultimate Markdown Showcase
  • Table of Contents
• Headings
• Heading 1
  • Heading 2
    • Heading 3
• Text Formatting
• Horizontal Rules
• Blockquotes
  • Quotes can contain Markdown
• Lists
  • Unordered
  • Ordered
  • Mixed
• Task Lists
• Links
• Images
• Tables
• Escaping Characters
• Code
  • Fenced code
  • Indented code
• Mathematics
• Footnotes
• Definition Lists
• Abbreviations
• Emoji
• HTML
• Keyboard Input
• Collapsible Code
• Mermaid Diagrams
• Block Diagram (ASCII)
• Nested Markdown
  • Nested Heading
• Raw HTML Table
• Entity References
• Automatic Line Breaks
• Sample Lorem Ipsum
• Final Checklist
  • Conclusion

title: “The Ultimate Markdown Showcase”
subtitle: “A deliberately over-engineered blog post for testing Markdown renderers”
author:
name: Jane Doe
email: jane@example.com
date: 2026-08-04
updated: 2026-08-05
tags:

• markdown
• testing
• preview
• documentation
  categories:
• Development
• Documentation
  draft: false
  published: true
  slug: ultimate-markdown-showcase
  description: >
  This file intentionally demonstrates as many Markdown features as possible
  to test Markdown preview software.
  keywords:
• markdown
• commonmark
• github flavored markdown
  license: CC-BY-4.0
  toc: true
  math: true
  mermaid: true

§The Ultimate Markdown Showcase

Goal: This document intentionally uses nearly every Markdown feature that a renderer might support.

Different Markdown engines support different extensions, so not every feature below will render everywhere.

§Table of Contents

• Text Formatting
• Lists
• Tables
• Code
• Math
• Images
• HTML
• Footnotes
• Task Lists
• Diagrams
• Emoji
• Definition Lists

§Headings

§Heading 1

§Heading 2

§Heading 3

§Heading 4

§Heading 5

§Heading 6

§Text Formatting

Normal paragraph text.

Bold

Also bold

Italic

Also italic

Bold + Italic**

Also Bold + Italic

Strikethrough

Underline (HTML)

==Highlighted== (supported by some renderers)

H2O (subscript in some implementations)

x^2^ (superscript in some implementations)

inline code

Keyboard shortcut:

Ctrl + Shift + P

Variable: x

Output:

Hello World

§Horizontal Rules

§Blockquotes

A simple quote.

Nested quote

Second level

Third level

§Quotes can contain Markdown

• Lists
• Formatting
• code

§Lists

§Unordered

• Apple
• Banana
  • Cavendish
  • Plantain
• Orange

• Alternative marker
• Another item

• Plus marker
• Another

§Ordered

1. First

2. Second

3. Third

4. Start

5. Auto numbering

6. Still works

§Mixed

1. Item
   • Nested bullet
   • Another
     1. Nested ordered
     2. Another

§Task Lists

• [x] Finished
• [x] Another completed item
• [ ] In progress
• [ ] Future work

§Links

Inline:

CommonMark

Reference:

GitHub

Automatic:

https://example.com

Email:

someone@example.com

Reference definition:

§Images

Inline image:

Image with title:

Clickable image:

§Tables

§Escaping Characters

*Not italic*

# Not a heading

`Not code`

\ Backslash

§Code

Inline: printf("Hello");

§Fenced code

from dataclasses import dataclass

@dataclass
class User:
    name: str
    age: int

def greet(user: User):
    print(f"Hello {user.name}")

greet(User("Alice", 42))

const greet = (name) => {
    console.log(`Hello ${name}`);
};

greet("World");

fn main() {
    println!("Hello, world!");
}

package main

import "fmt"

func main() {
    fmt.Println("Hello")
}

SELECT *
FROM users
WHERE active = TRUE
ORDER BY created_at DESC;

{
  "name": "Markdown",
  "version": 1,
  "enabled": true,
  "items": [1,2,3]
}

name: Markdown
version: 1
features:
  - tables
  - math
  - footnotes

- old line
+ new line
 unchanged

echo "Hello"
ls -la

§Indented code

function hello() {
    return true;
}

§Mathematics

Inline:

\(E = mc^2\)

Block:

$$ \int_0^\infty e^{-x} dx = 1 $$

Matrix:

$$ \begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix} $$

Aligned equations:

$$ a+b &= c \\ x+y &= z $$

§Footnotes

Markdown supports footnotes in many implementations.¹

Another reference.²

§Definition Lists

Term 1
: Definition 1

Term 2
: Definition A
: Definition B

§Abbreviations

*[HTML]: HyperText Markup Language
*[CSS]: Cascading Style Sheets

HTML and CSS appear here.

§Emoji

Unicode:

😀 🚀 🎉 ❤️ 🌍

Shortcodes (renderer dependent):

:smile:
:rocket:
:heart:

§HTML

Progress:

Meter:

70%

Text with:

highlight

small text

^superscript

_subscript

§Keyboard Input

Press Ctrl + C to copy.

§Collapsible Code

Hidden code block.

§Mermaid Diagrams

flowchart TD

A(Start) --> B{Decision}

B -->|Yes| C[Success]

B -->|No| D[Failure]

C --> E(End)

D --> E

sequenceDiagram

Alice->>Bob: Hello Bob

Bob-->>Alice: Hi Alice

gantt
title Project

dateFormat YYYY-MM-DD

section Planning

Research :done, 2026-08-01,2d

Design :active,2026-08-03,5d

§Block Diagram (ASCII)

+-----------+
|   Input   |
+-----+-----+
      |
      v
+-----------+
| Processor |
+-----+-----+
      |
      v
+-----------+
|  Output   |
+-----------+

§Nested Markdown

§Nested Heading

print("Nested code")

• Nested list
• Another item

§Raw HTML Table

§Entity References

Copyright: ©

Arrow: →

Heart: ♥

Euro: €

§Automatic Line Breaks

Line one.
Line two using two spaces.

Line three using a blank line.

§Sample Lorem Ipsum

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum nec orci ac lectus pretium tristique. Integer nec lacus ut erat malesuada porta. Curabitur efficitur sapien sit amet lorem dignissim, nec posuere metus feugiat.

§Final Checklist

§Conclusion

If your Markdown renderer correctly displays everything above—including tables, syntax highlighting, math, Mermaid diagrams, footnotes, HTML, task lists, definition lists, and collapsible sections—then it supports a very broad set of Markdown and Markdown-extension features.

Happy testing! 🚀