MDX Data & Text — A .mdx file is a MDX Data & Text. It is a text-based data format widely used for configuration files, data interchange and API payloads.
Quick facts
What is .mdx
A .mdx file is a MDX Data & Text. It is a text-based data format widely used for configuration files, data interchange and API payloads.
In the mime-db registry it maps to text/mdx, and it is marked as compressible. When serving .mdx over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to text/mdx and is used by MDX among others — and is delivered over HTTP via the Content-Type header.
How to open .mdx files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: text/mdx
Common software that reads/writes .mdx:
Relation chain
Related extensions
Related MIME types
Related programming languages
Common uses
How to edit .mdx files
How to create .mdx files
Frequently asked questions
Common options include VS Code, Notepad++, Sublime Text. 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 .mdx extension.
text/mdx is the media type identifier used for .mdx files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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