Why convert STL to GLB?
STL is raw triangle soup: every triangle is stored independently with no shared vertices, no materials, and no UV coordinates. It is fine for a slicer but heavy and unviewable on the web.
GLB gives you an indexed, compressed mesh that loads in browsers, AR viewers, and game engines — with room for color and PBR materials if you add them.
What Zlim optimizes
Zlim welds coincident vertices into a proper indexed mesh, removes degenerate and duplicate triangles, recomputes normals where needed, then quantizes and Draco-compresses the geometry. Because STL carries no textures, the win here is geometry: a large STL routinely becomes a GLB a fraction of its size while looking identical.
zlim optimize part.stl -o part.glb -p balanced # cleans + indexes + compresses → part.glbFAQ
Can I add color or materials?
STL has none to begin with. The GLB output supports PBR materials, so you can assign them downstream; Zlim focuses on producing clean, compressed geometry.
Does Zlim handle both binary and ASCII STL?
Yes — both STL variants are accepted and produce the same optimized GLB.
Convert STL to GLB now
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