F90 Data & Text — A .f90 file is a F90 Data & Text. It is a text-based data format widely used for configuration files, data interchange and API payloads.
Quick facts
What is .f90
A .f90 file is a F90 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/x-fortran. When serving .f90 over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to text/x-fortran and is used by Fortran Free Form among others — and is delivered over HTTP via the Content-Type header.
How to open .f90 files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: text/x-fortran
Common software that reads/writes .f90:
Relation chain
Related extensions
Related MIME types
Related programming languages
Common uses
How to edit .f90 files
How to create .f90 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 .f90 extension.
text/x-fortran is the media type identifier used for .f90 files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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