Convert ASCII STL files to compact binary STL — typically 5× smaller. Faster to load, cheaper to store. 100% browser-based, no upload.
Upload your ASCII STL file
STLLoader detects the format and parses triangle data
Download the binary STL — same geometry, ~5× smaller
0 bytes uploaded. STL ASCII → Binary Converter runs entirely in your browser using three.js and WebGL. Your meshes never leave your device.
ASCII STL stores each float as text (e.g. "vertex 1.234567"). Binary STL packs each float into 4 raw bytes. The size ratio is roughly 5:1 for typical models.
Yes. The conversion is lossless — both formats represent the same triangle list with the same precision.
Yes. Binary STL is the de facto default for 3D printing slicers and CAD tools. ASCII is only used for human-readable debugging.
Convert binary STL files to human-readable ASCII STL. Diff models, version-control geometry, or debug malformed meshes. Browser-based.
Open toolConvert STL files to GLB (binary glTF) directly in your browser. Smaller, faster, and AR-ready. Zero upload — your meshes never leave your device.
Open toolConvert STL meshes to Wavefront OBJ in your browser. Open the result in Blender, Maya, Cinema 4D, or any 3D tool. Privacy-first — zero upload.
Open tool