STL to OBJ Converter — Convert Locally in Your Browser

Who this is for: For anyone holding a STL file that needs to become OBJ: a pipeline or tool that prefers OBJ. Nothing is lost — STL has only triangles, and OBJ stores at least that much. The OBJ simply carries the same mesh without materials.

Convert STL to OBJ in your browser — drop the file, the mesh loads instantly, download the OBJ. Nothing uploaded, free and unlimited.

Quick answer: The free STL to OBJ converter loads your file in the browser, renders the mesh in 3D so you can check it, and exports a clean OBJ — no upload, no account, no limits. Nothing is lost — STL has only triangles, and OBJ stores at least that much. The OBJ simply carries the same mesh without materials.

Drop a STL file hereor click to choose · up to 30MB

Core facts

Input	STL file up to 30MB — Triangle mesh only (vertices + face normals)
Output	OBJ — Mesh with optional material file (.mtl) and texture references
What carries over	Geometry (all triangles), exactly as loaded
What does not	Nothing is lost: STL has only triangles, and OBJ stores at least that much. The OBJ simply carries the same mesh without materials.
Cost	Free and unlimited — runs in your browser
Privacy	Nothing uploaded — the file never leaves your device

STL to OBJ, and what changes in the swap

Stereolithography (STL) stores: triangle mesh only (vertices + face normals). Wavefront OBJ (OBJ) stores: mesh with optional material file (.mtl) and texture references. Everything both formats share travels over completely when you convert here — the mesh — and the preview shows exactly what arrives on the other side before you commit to a download.

Nothing is lost — STL has only triangles, and OBJ stores at least that much. The OBJ simply carries the same mesh without materials.

This conversion runs entirely in your browser using the same WebGL engine that renders the preview: load the STL, inspect it from every angle, export the OBJ. Because nothing is uploaded and no server computes the conversion, there is no size-based price, no queue, and no daily limit — converters on this site are free without asterisks. The only practical ceiling is your own device's memory (files up to 30MB load comfortably).

Common uses

Opening a STL in tools that prefer OBJ
Moving a print-ready mesh into a modeling or rendering pipeline
Publishing a OBJ to a viewer or store that expects it
Archiving your prints in the friendlier OBJ container

Frequently Asked Questions

How do I convert STL to OBJ?

Drop your STL file into the converter on this page — it loads and converts entirely in your browser, then you download the OBJ. No upload, no account, no queue. Files up to 30MB work; bigger files depend on your device's memory.

Is OBJ smaller or bigger than STL?

Comparable mesh data, small container differences — the real size differences come from what each format can store (OBJ: referenced (uvs + image files)).

Do I lose color or textures?

In this direction: nothing from the geometry; colors exist only if the source format had them and the target can carry them.

Are my files uploaded?

No. The converter runs entirely in your browser using WebGL technology — your file never leaves your device. That is also why it is free with no limits: there is no server cost per conversion.

Will the scale (units) change?

STL has none (numbers only — slicers assume mm); OBJ has none (numbers only). No conversion tool can invent units that were not stored — check the part's size in your slicer and set scale there if needed.

Why would I go STL to OBJ?

Because OBJ opens doors STL does not: DCC tools that import OBJ but choke on huge STLs, pipelines that expect a .mtl path, or downstream tools where you will add materials. The geometry is identical; OBJ is simply the more extensible container.

More guides

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