P21 3D Model — A .p21 file is a P21 3D Model. It is a 3D model format used to store meshes, scenes and printing geometry.
Quick facts
What is .p21
A .p21 file is a P21 3D Model. It is a 3D model format used to store meshes, scenes and printing geometry.
In the mime-db registry it maps to model/step. When serving .p21 over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to model/step — and is delivered over HTTP via the Content-Type header.
How to open .p21 files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: model/step
Common software that reads/writes .p21:
Relation chain
Related extensions
Related MIME types
Common uses
How to edit .p21 files
How to create .p21 files
Frequently asked questions
Common options include Blender, MeshLab, Autodesk Viewer. 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 .p21 extension.
model/step is the media type identifier used for .p21 files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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