Free 3D File Compressor Online

On the default Lossless tier, yes — for visible geometry, compression is fully lossless. The optimizer removes duplicate vertices, merges redundant materials, and prunes unused nodes, but never discards, simplifies, or approximates any mesh data. The optional Balanced and Maximum tiers, offered on GLB, GLTF, and FBX, are lossy by design: they add Draco geometry compression and re-encode textures to WebP to shrink files far more, at the cost of a small, controlled loss of precision.

Results depend on the format, the file's redundancy, and the tier you choose. On the default Lossless tier, a clean, well-exported GLB often does not shrink at all because there is no redundant data left to remove; files that do carry duplicate vertices or unused scene data typically come down 0–20%. The Balanced and Maximum tiers, available for GLB, GLTF, and FBX, shrink textured models by 60–98% by adding Draco geometry compression and re-encoding textures to WebP. OBJ, STL, and PLY benefit mainly when they are stored as ASCII: re-encoding them to binary often shrinks them several-fold. If an STL or PLY is already binary there is usually nothing left to remove and it may not shrink at all — in that case you get your original file back rather than a larger one.

Absolutely. Every run writes a standard file in the format you chose: a fully standards-compliant binary glTF file for GLB, GLTF, and FBX runs that use the GLB container, an FBX file for FBX runs that keep the FBX container, and the original format for OBJ, STL, and PLY. All of them work with Three.js, Babylon.js, Unity, Unreal Engine, Godot, and virtually all modern 3D engines and web viewers — no special import settings needed.