Free tools

Converters that run in your browser.

Small, honest utilities built on three.js. Your file is parsed on your machine, previewed, and written back out. No upload, no account, no watermark. They exist because we needed them while building the generator.

Choose a tool for the result you need.

Start with image to STL for a raised graphic or plaque, or JPG to STL for a flat photographic lithophane. Both map brightness to thickness and include editable dimensions, tone controls and a sample image. They create rectangular reliefs from the visible picture.

For an existing 3D model, choose by source and destination. 3MF to STL extracts manufacturing geometry; GLB to STL makes a static print-oriented export with a scale control, and GLB to OBJ keeps the metre, Y-up frame for modelling tools. FBX to OBJ and STL to OBJ produce static mesh geometry, while OBJ to GLB and OBJ to STL ask for explicit source units and up axis because OBJ declares neither.

Before slicing any STL, run it through the STL checker. It reports triangles, welded vertices, millimetre dimensions, surface area, signed volume, boundary and non-manifold edges, winding consistency and tiny triangles, and lets you download the report as JSON.

Inspect before using the converted file.

A format change preserves only what the destination can represent. STL omits colors, materials and animation. These OBJ and GLB conversions focus on static geometry and do not recreate a texture package or add a rig. Each tool explains its supported inputs, limits, format losses and validation.

Compare the dimensions and expected parts, then check the download in your destination application. Printing also needs a sliced-layer review and suitable walls, orientation and material settings. A successful conversion is not an automatic mesh repair.

The free converters process files locally in your browser; nothing is uploaded and no account is needed. Images are limited to 32 MiB; model inputs are limited to 64 MiB, with further bounds on expanded geometry. They do not spend generation credits. Every tool page lists its inputs, outputs, controls and limits, and its guide ends with what the automated tests cover. Learn how we separate tested behavior from broader goals on the Bake3D validation page.