How to Edit Markdown Online Free — Live Preview (2026)

The brevio Markdown Editor gives you a live two-panel editor: type Markdown on the left, see rendered HTML on the right. Toolbar shortcuts for common syntax. Word and character count. Runs entirely client-side — your content never leaves your browser.

Markdown Syntax Quick Reference

How to Use the Markdown Editor Step by Step

1. Open the Markdown Editor. It loads with a sample document so you can see the two-panel layout immediately.
2. Clear the sample and start typing. The right panel updates live on every keystroke.
3. Use toolbar shortcuts. Click B to wrap the selected text in **...** for bold. I for italic. Backtick for inline code. H inserts a heading prefix. The link and list buttons insert syntax at the cursor.
4. Check word and character count below the editor panels.
5. Copy your content. Select all in the left panel and copy, or select the rendered HTML in the right panel.

Markdown Table Syntax

| Name       | Role     | Status  |
|------------|----------|---------|
| Alice      | Engineer | Active  |
| Bob        | Designer | On leave|

The second row of hyphens and pipes creates the table header separator. Column widths are determined by the longest cell in each column. Alignment can be set with colons: :--- for left, :---: for center, ---: for right.

Markdown Fenced Code Blocks

```javascript
function greet(name) {
  return `Hello, ${name}!`
}
```

The language identifier after the opening backticks enables syntax highlighting in most Markdown renderers. Common identifiers: javascript, python, bash, css, html, json, typescript.

Markdown vs HTML: When to Use Each

Markdown is a lightweight text-to-HTML conversion format best suited for documentation, blog posts, README files, and content that will be processed by a Markdown parser. You can embed raw HTML directly in most Markdown documents when you need features Markdown does not support (custom classes, span styling, complex tables). However, mixed Markdown/HTML can break some parsers — prefer pure Markdown for portability.

Where Markdown Is Used

• GitHub/GitLab: README.md, pull request descriptions, comments, wikis
• Documentation tools: Docusaurus, MkDocs, Notion, Obsidian
• Static site generators: Next.js (MDX), Hugo, Jekyll, Gatsby
• Messaging apps: Slack, Discord (partial support)
• Email clients: Some clients support Markdown via plugins

Frequently Asked Questions

What Markdown flavour does this editor use?

The editor uses the marked library which follows CommonMark with GitHub Flavored Markdown (GFM) extensions including tables, strikethrough, task lists, and fenced code blocks. This matches what GitHub renders.

Can I export the rendered HTML?

Yes — right-click the preview panel and select "View Page Source" or "Inspect" to access the rendered HTML. Alternatively, select all in the preview panel and copy — most clipboard managers capture formatted HTML.

How do I add line breaks in Markdown?

A blank line between paragraphs creates a new paragraph. For a line break within a paragraph (soft break), end the line with two spaces before pressing Enter. The HTML <br> tag also works directly in Markdown.

Is Markdown safe from XSS?

This editor renders Markdown client-side in a sandboxed dangerouslySetInnerHTML div with no server round-trip, so there is no XSS vector from server processing. If you copy the HTML output to use elsewhere, sanitise it before inserting into a DOM that trusts untrusted content.