Markdown Previewer Guide: Write & Export Markdown

What this guide covers

Markdown is a plain-text formatting syntax that turns into HTML. This is a practical reference to the syntax you will use most, with each snippet ready to paste into the Markdown Previewer so you can watch it render live.

Headings

Use one to six # characters for heading levels one to six, followed by a space.

# Title
## Section
### Subsection

Emphasis and inline styles

*italic* or _italic_ for italic.
**bold** for bold, and ***bold italic*** for both.
~~strikethrough~~ crosses text out (a GitHub extension).
Backticks make `inline code`.

Lists

Start unordered items with -, * or +; start ordered items with a number and a dot. Indent to nest a sub-list.

- First
- Second
  - Nested item
1. Step one
2. Step two

GitHub-style task lists use - [ ] for an empty checkbox and - [x] for a checked one.

Links and images

A link is [text](https://example.com). An image is the same with a leading !: ![alt text](/path/to/image.png). Always write real alt text so the image is described when it cannot be shown.

Blockquotes and rules

> A quoted line.
> > A nested quote.

---

Three dashes on their own line draw a horizontal rule.

Code blocks

Wrap a block in three backticks. Add a language name after the opening fence for syntax highlighting on platforms that support it.

```js
console.log("hello");
```

Tables

Separate columns with pipes and mark the header with a row of dashes. Colons set the column alignment.

| Tool           | Free  |
| -------------- | :---: |
| JSON Validator | yes   |

Line breaks: the common gotcha

A single newline usually does not start a new line in the output. To force a line break, end a line with two spaces, or leave a blank line to begin a new paragraph. This is the mistake that trips people up most.

Escaping special characters

To show a character that Markdown would otherwise treat as formatting, put a backslash before it: \*not italic\*. That works for literal asterisks, underscores, backticks, hashes and brackets.

CommonMark and GitHub-flavored Markdown

The core syntax is standardised as CommonMark. GitHub-Flavored Markdown (GFM) adds tables, task lists, strikethrough and automatic links. The previewer supports CommonMark plus the common GFM extensions, so what renders here matches what most platforms produce. When you are done, Copy HTML puts the rendered markup on your clipboard and Download .html saves a standalone file, all without anything leaving your browser.

FAQ

What Markdown does it support?

CommonMark plus common GitHub-style extensions, via the marked parser.

Can I export the result?

Yes — copy the HTML or download a complete file.

Is my text uploaded?

No — it's parsed entirely in your browser.

Ready to try it? Open the Markdown Previewer →

Markdown Previewer: write, preview, export