SIG Data & Text — A .sig file is a SIG Data & Text. It is a text-based data format widely used for configuration files, data interchange and API payloads.
Quick facts
What is .sig
A .sig file is a SIG 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 application/pgp-signature. When serving .sig over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to application/pgp-signature and is used by Standard ML among others — and is delivered over HTTP via the Content-Type header.
How to open .sig files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: application/pgp-signature
Common software that reads/writes .sig:
Relation chain
Related extensions
Related MIME types
Related programming languages
Common uses
How to edit .sig files
How to create .sig 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 .sig extension.
application/pgp-signature is the media type identifier used for .sig files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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