About STL File Converter

What this site is

STL File Converter is a free online tool for converting 3D model files between the formats makers actually use: STL, OBJ, GLB, glTF, and 3MF. Drop a file on the homepage, preview it in 3D, pick a target format, and download the result.

How it works

Every conversion runs entirely in your browser, on your device, using the same proven open-source 3D engine (three.js) that powers much of the 3D web. Your files are never uploaded to a server — there is nothing to leak, nothing to queue behind, and nothing to sign up for.

Why we built it

Most online converters route your model through a server: slow uploads, file size caps, watermarks, or a paywall after three conversions. We wanted the opposite — a converter that feels like opening a desktop app, but lives at a URL.

What it costs

Nothing. The converter is free, without accounts, credits, or download limits.