Markdown Document — Lightweight markup for formatted plain text.
Quick facts
What is .md
A .md file is a Markdown Document — Lightweight markup for formatted plain text.
In the mime-db registry it maps to text/markdown, and it is marked as compressible. When serving .md over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to text/markdown and is used by GCC Machine Description, Markdown among others — and is delivered over HTTP via the Content-Type header.
How to open .md files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: text/markdown
Common software that reads/writes .md:
Relation chain
Related extensions
Related MIME types
Related programming languages
Common uses
How to edit .md files
How to create .md files
Example
# Heading A paragraph with **bold** and a [link](https://refnet.dev).
Frequently asked questions
Common options include VS Code, Typora, GitHub. You can also open many of these files with built-in viewers or a browser.
Create a new file in any text editor or the app that owns the format and save it with the .md extension.
text/markdown is the media type identifier used for .md files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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