OBJ File — What It Is and What Opens It

What OBJ is

OBJ is a plain-text format you can open in any editor. It stores shapes and coordinates rather than pixels, so it stays sharp at any size — a logo scaled to a billboard loses nothing. It is used for moving data between programs and editing.

The extension is .obj, and the full name is Wavefront Object. Both matter less than what the file can hold, which is what the rest of this page is about.

Where OBJ came from

Wavefront Technologies published it in 1992.

A format that has been readable for that long is a format worth trusting with something you want back in ten years.

The specification is public

Anyone can implement it without asking permission or paying a licence, which is why it turns up in so many programs and why files written twenty years ago still open.

Nothing is thrown away

OBJ stores its content exactly. Saving it again changes nothing, so it can be opened, edited and re-saved as often as you like without accumulating damage — which is what makes it a working format rather than a delivery one.

What opens OBJ

Blender, MeshLab and Maya read it, and so do most programs of the same kind.

If a file will not open, the format is rarely the problem — it is more often that the program predates it. Converting to something older is the reliable way past that, and it is what the rest of this site is for.

Opening it in a browser

No browser reads it.

That is the single most common reason to convert it: not that the format is bad, but that the place you want to show the file cannot read it.

It is a working format

OBJ is meant to be opened and changed. Keep the file in this format for as long as the work is going on, and export from it whenever a finished copy is needed.

The facts, in one place

Identifiers and provenance for the OBJ format.
Extension	.obj
Media type	model/obj
Published by	Wavefront Technologies
First published	1992

What is an OBJ file?