What's the difference between CommonMark and GFM?

CommonMark is the official Markdown spec — covers basic syntax (headings, lists, emphasis, links, code). GitHub Flavored Markdown (GFM) extends CommonMark with: tables, task lists (- [x] done), strikethrough (~~text~~), autolinks, and fenced code blocks with language hints. Most modern Markdown processors support GFM by default.

Does Markdown allow HTML?

Yes — most parsers pass HTML through unchanged. You can write Ctrl+C , , , directly in Markdown. Some platforms (GitHub, GitLab, Reddit) sanitize HTML for security, stripping , event handlers, and other dangerous tags. When in doubt, prefer pure Markdown.

How do I escape Markdown characters?

Use a backslash before any of: \\ \` * _ {} [] () # + - . ! |. So \* renders literal asterisk instead of starting italics. Inside code spans (`like this`) escaping isn't needed — content is rendered verbatim.

Why aren't my line breaks rendering?

Markdown collapses single newlines into spaces. To force a line break: end the line with two trailing spaces, or use . To start a new paragraph: leave a blank line between blocks. Some processors (GFM) auto-break on single newlines inside lists or quotes — consult your platform's docs.

Where is Markdown used in 2026?

Everywhere: GitHub README and issues, Reddit posts, Discord/Slack messages (limited subset), Notion, Obsidian, Roam, Bear, static site generators (Jekyll, Hugo, Gatsby, Astro), documentation tools (Docusaurus, MkDocs, GitBook), and AI chat interfaces. It's effectively the lingua franca of structured plain text.

Markdown Cheat Sheet

Complete markdown reference: headings, emphasis, lists, links, code blocks, tables, and GFM extensions like task lists and strikethrough.

Headings

Markdown	Result
# H1	Largest heading
## H2	Second-level
### H3	Third-level
#### H4 / ##### H5 / ###### H6	Smaller

Emphasis

Markdown	Result
italic or _italic_	italic
bold or __bold__	bold
*bold italic*	*bold italic*
~~strike~~ (GFM)	~~strike~~
`code`	`code`

Lists

Markdown	Notes
- Item - Item - Nested	Unordered (or use * or +)
1. First 2. Second 3. Third	Ordered (numbers don't need to match output)
- [ ] Todo - [x] Done	Task list (GFM)

Links and images

Markdown	Notes
[label](https://example.com)	Inline link
[label](https://example.com "Title")	Link with hover title
![alt text](image.png)	Inline image
<https://example.com>	Auto-link (URL becomes clickable)
[label][ref] [ref]: https://example.com	Reference-style link

Code blocks

Markdown	Notes
``` code block ```	Fenced code block
```js const x = 1; ```	With syntax highlighting (GFM)
indent 4 spaces	Indented code block (older style)

Tables (GFM)

| Col 1   | Col 2   | Col 3   |
| ------- | :-----: | ------: |
| left    | center  | right   |
| default | aligned | aligned |

Colons in the divider row set alignment: :--- left, :---: center, ---: right.

Blockquotes & rules

Markdown	Notes
> Single quote > spans lines. >> Nested.	Blockquote
---	Horizontal rule (also *** or ___)

Escaping & line breaks

Markdown	Notes
\* literal asterisk	Backslash escapes
Line one Line two	Two trailing spaces = line break
Para 1 Para 2	Blank line = new paragraph

Try writing markdown live in our Markdown Editor with side-by-side preview.

Markdown Cheat Sheet — Complete Syntax Reference for Developers and Writers

Markdown is the universal plain-text formatting language that powers GitHub READMEs, technical documentation, blog posts, Notion pages, Obsidian notes, Discord messages, and AI chat interfaces. It adds enough structure to be genuinely useful — headings, lists, bold, code blocks, links, tables — without the verbosity of HTML or the complexity of LaTeX. Once you know it, you write faster in every tool that supports it.

How to use this cheat sheet

Skim the section that matches your need — headings, emphasis, lists, links, code blocks, tables, or blockquotes. Each row shows the Markdown syntax alongside the rendered result or a description. Special attention is given to GFM (GitHub Flavored Markdown) extensions — task lists, strikethrough, and fenced code blocks with language syntax highlighting — since most platforms you encounter today support GFM rather than basic CommonMark. For all features with subtle syntax rules (tables, line breaks, escaping), the Notes column explains the gotchas that trip up beginners.

CommonMark vs GFM — what you need to know

CommonMark is the official Markdown specification that standardises core syntax across all processors. GitHub Flavored Markdown (GFM) extends CommonMark with features that have become essential in modern workflows: tables with column alignment, task lists (- [x] done), strikethrough (~~text~~), automatic URL linking, and fenced code blocks with language identifiers for syntax highlighting. Most modern Markdown processors — GitHub, GitLab, Notion, Obsidian, MkDocs, Docusaurus, and many others — support GFM as their baseline. When in doubt, stick to CommonMark syntax for maximum portability, and treat GFM features as opt-in enhancements.

Who uses this cheat sheet

Developers who write GitHub READMEs and pull request descriptions use it as a quick lookup when they need to format a table or remember the fenced code block syntax. Technical writers use it when documenting APIs in MkDocs, Docusaurus, or GitBook and need to verify syntax for their chosen processor. Bloggers writing in static site generators like Hugo, Jekyll, or Astro use it when they encounter formatting questions mid-draft. Students and professionals using Obsidian or Notion for personal knowledge management use it to unlock the full power of Markdown linking and structure.

Privacy and data handling

This is a static reference page — it contains no interactive elements that collect input, and no user data is transmitted to any server.

Frequently asked questions

What's the difference between CommonMark and GFM?: CommonMark is the official Markdown spec — covers basic syntax (headings, lists, emphasis, links, code). GitHub Flavored Markdown (GFM) extends CommonMark with: tables, task lists (- [x] done), strikethrough (~~text~~), autolinks, and fenced code blocks with language hints. Most modern Markdown processors support GFM by default.
Does Markdown allow HTML?: Yes — most parsers pass HTML through unchanged. You can write <kbd>Ctrl+C</kbd>, <details>, <iframe>, <video> directly in Markdown. Some platforms (GitHub, GitLab, Reddit) sanitize HTML for security, stripping <script>, event handlers, and other dangerous tags. When in doubt, prefer pure Markdown.
How do I escape Markdown characters?: Use a backslash before any of: \\ \` * _ {} [] () # + - . ! |. So \* renders literal asterisk instead of starting italics. Inside code spans (`like this`) escaping isn't needed — content is rendered verbatim.
Why aren't my line breaks rendering?: Markdown collapses single newlines into spaces. To force a line break: end the line with two trailing spaces, or use <br>. To start a new paragraph: leave a blank line between blocks. Some processors (GFM) auto-break on single newlines inside lists or quotes — consult your platform's docs.
Where is Markdown used in 2026?: Everywhere: GitHub README and issues, Reddit posts, Discord/Slack messages (limited subset), Notion, Obsidian, Roam, Bear, static site generators (Jekyll, Hugo, Gatsby, Astro), documentation tools (Docusaurus, MkDocs, GitBook), and AI chat interfaces. It's effectively the lingua franca of structured plain text.