How to write code blocks in Markdown
Try it — edit the markdown and watch the preview
Result
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Three backticks open and close a code block. A language name after the opening fence turns on syntax highlighting:
```js
const site = 'allmarkdown.com';
```
Inside a block, nothing is interpreted as Markdown. Asterisks stay asterisks and underscores stay underscores, which is exactly what you want when the content is code, a file path or a configuration snippet.
Inline code
Single backticks mark a span inside a sentence: `npm run build`. Use it
for anything the reader might copy — commands, filenames, function names,
literal values.
When the code contains backticks
Use more backticks on the outside than appear on the inside:
- two backticks wrap a span containing one
- a four-backtick fence wraps a block containing a three-backtick fence
That is how the example at the top of this page is written.
Indented blocks still work
Four leading spaces also make a code block. It is the original syntax and it still parses, but it cannot carry a language name and it is easy to confuse with list indentation. Fenced blocks are the better default.
Common questions
- How do I write a code block?
- Put three backticks on the line before and the line after the code. Add a language name after the opening fence — ```js — and most renderers will syntax-highlight it.
- What is the difference between inline code and a code block?
- Single backticks mark a short span inside a sentence, which stays in the flow of the paragraph. Triple backticks create a separate block that preserves line breaks and indentation exactly.
- How do I show backticks inside a code span?
- Use more backticks on the outside than appear on the inside. Two backticks can wrap a span containing one, and a four-backtick fence can wrap a block containing a three-backtick fence.
- What language names are supported?
- That depends on the renderer rather than on Markdown. Common ones — js, ts, python, bash, json, yaml, sql, go, rust, html, css — are near-universal. An unrecognised name is not an error; the block simply renders unhighlighted.
- Is indenting four spaces still valid?
- Yes, and it is the original syntax, but it cannot carry a language name and it collides with list indentation. Fenced blocks are clearer and are what almost everyone writes now.