CPIO Archive — A .cpio file is a CPIO Archive. It is a compressed archive format that bundles files for easier storage and distribution.
Quick facts
What is .cpio
A .cpio file is a CPIO Archive. It is a compressed archive format that bundles files for easier storage and distribution.
In the mime-db registry it maps to application/x-cpio. When serving .cpio over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to application/x-cpio — and is delivered over HTTP via the Content-Type header.
How to open .cpio files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: application/x-cpio
Common software that reads/writes .cpio:
Relation chain
Related extensions
Related MIME types
Common uses
How to edit .cpio files
How to create .cpio files
Frequently asked questions
Common options include 7-Zip, WinRAR, tar. 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 .cpio extension.
application/x-cpio is the media type identifier used for .cpio files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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