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