Learn Markdown — the complete guide

Markdown is the lightweight text format behind every README on GitHub, every Notion page, every Discord message with **bold** in it, and the output of every modern AI assistant. This guide takes you from "what is Markdown" to "I exported a polished PDF in two clicks" — with a video, a syntax cheat sheet, and deeper reading for each topic.

1. What Markdown is — and why people use it

Markdown is a plain-text formatting syntax. You write **bold** in your file; it renders as bold in a browser. You write # Heading; it becomes a heading. Unlike Word or Google Docs, the formatting characters are visible in the source — which is exactly the point.

Three advantages keep it dominant:

Plain text. Works in any editor, any platform, any version-control system. A Markdown file diffs cleanly in git; a .docx doesn't.
Readable as source. Nobody needs to render **bold** to know what it means.
Convertible. The same source becomes HTML, PDF, DOCX, a slide deck, or a static site. Write once, render anywhere.

For the long version, see What is Markdown? A complete guide.

2. The syntax you'll use 95% of the time

The full surface is short enough to fit on one screen:

# Heading 1
## Heading 2
### Heading 3

**Bold** and *italic* and ~~strikethrough~~.

Inline `code` and code blocks:

```python
print("fenced — three backticks")
```

- Unordered list item
- Second item
  - Nested

1. Ordered list
2. Second item

> Blockquote.

[Link text](https://example.com)
![Alt text](/image.png)

| Header | Cell |
| ------ | ---- |
| Body   | …    |

That's the CommonMark core. Task lists (- [ ] todo), footnotes, and math are flavor-specific extensions covered in the complete Markdown syntax cheat sheet.

3. CommonMark, GFM, and the other flavors

Markdown is not one spec. The variants you'll meet:

CommonMark — the formal core. Everyone supports it.
GitHub Flavored Markdown (GFM) — CommonMark + tables, task lists, strikethrough, autolinks. The de-facto online standard. See GitHub Flavored Markdown: what's different.
Pandoc / MultiMarkdown — adds footnotes, citations, math. Academic territory.
Discord, Slack, Notion — subsets with platform-specific quirks. See Discord, Slack, and Notion vs Obsidian vs Typora.

4. Editors, viewers, and converters

Markdown files (.md) open in any text editor. Dedicated apps add live preview and export features. The most common picks:

Editors: Typora, Obsidian, iA Writer, MacDown. Comparison: 7 Typora alternatives.
Viewers: any browser via a Markdown viewer, or natively on GitHub.
Converters: command-line tools like Pandoc; web converters like Markdown Tidy; libraries like markdown-it (JS) and Python-Markdown.
Documentation sites: MkDocs, Docusaurus, Astro, Hugo — all consume Markdown.

5. Exporting to PDF, Word, HTML

The point of Markdown is rarely Markdown itself. It's the rendered output:

Markdown to PDF — the most common conversion.
Markdown to Word (.docx) — for stakeholders who want an editable Word file.
Markdown to HTML — for web or email.

The trap is that most converters work fine on clean Markdown and fall apart on real-world AI output. That's the gap Markdown Tidy fills — paste the source, let it repair broken tables and stray characters, export the result.

Open the editor →

6. Cleaning AI-generated Markdown

ChatGPT, Claude, and friends emit Markdown that looks fine in chat but breaks in any serious renderer — broken tables, mismatched fences, smart quotes that confuse code blocks, non-standard list markers, etc. Common patterns and fixes:

Next steps

Two paths from here. If you have content to clean right now: open the editor. If you want to learn more first: the blog index has 29 posts on every Markdown topic worth knowing.