CDX Other — A .cdx file is a CDX Other. It is a file format typically read and written by specialized applications.
Quick facts
What is .cdx
A .cdx file is a CDX Other. It is a file format typically read and written by specialized applications.
In the mime-db registry it maps to chemical/x-cdx. When serving .cdx over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to chemical/x-cdx — and is delivered over HTTP via the Content-Type header.
How to open .cdx files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: chemical/x-cdx
Common software that reads/writes .cdx:
Relation chain
Related extensions
Related MIME types
Common uses
How to edit .cdx files
How to create .cdx files
Frequently asked questions
Common options include VS Code, xxd, 7-Zip. 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 .cdx extension.
chemical/x-cdx is the media type identifier used for .cdx files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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