OpenGeometry
A CAD geometry kernel built to be driven by people and by AI agents alike.
What it does and how it connects
OpenGeometry is an open-source CAD kernel for the browser. It models B-rep solids, runs boolean operations (union, subtract, intersect), builds solids by extrude, sweep and revolve, and writes STEP files. The kernel is written in Rust and compiled to WebAssembly, and a TypeScript SDK for Three.js puts every body straight into the scene.
It is the geometry engine layer, not a full CAD application, and is best suited for browser-based CAD, configurators and geometry-heavy web tools. The README describes OpenGeometry 3.0.0 and notes the hosted documentation still describes 2.0, and that the 2.0 line has a different API, so users should check which line they have installed.
Floorkit is a downstream application and toolkit built on top of OpenGeometry for AEC workflows. In this repository, OpenGeometry is the primary SDK and engine. The README states the project is actively maintained and growing, with APIs, examples and package structure evolving.
What engineers report
Subtracting a small radial cylinder from a quarter tube returns the tube unchanged, with the same 6 faces as the input and no hole, while larger holes on the same axis cut correctly.
2026-11-01Read the original
Alternatives
Compare side by side- SolidCraft (tangency-labs)
An open-source parametric 3D CAD application in Rust with a built-in MCP server, rather than a browser-native CAD geometry kernel.
- OpenCADStudio
A Rust CAD program for 2D and 3D drawing with DWG and DXF support and an MCP endpoint, rather than a browser-native CAD geometry kernel.
- CadQuery
A Python library for building parametric 3D CAD models with scripts, exporting STEP and STL, rather than a browser-native CAD kernel for web apps and AI CAD.
- build123d
A Python-based parametric B-rep modeling framework for CAD-as-code workflows, rather than a browser-native CAD kernel.
Recurring errors it addresses
Error Index entries this tool is built to reduce or work around.
- STEP export wrote full cylinders, through-hole walls and cones with two ring wires but no seam or UV associations, and raw OpenCASCADE import rejects them.Error Index
- When a STEP file declares uncertainty over about 6.283 mm (2 pi), a cone ending in an apex reads back wrong, invalid solid or zero-area conical face, with no error or warning from the reader.Error Index
Sources
Not verified
- Pricing: none stated on the repo; the package is free open source.
- Version note: the latest release is v0.0.7 from 2025-10-08, from the old 2.0 line, while the README describes 3.0.0; the release tag does not reflect the current README version.
- Related errors are STEP-format matches, since no OpenGeometry-specific Error Index entry exists.
Last verified November 6, 2026. Listings are informational. The evidence score measures public, verifiable evidence and is not an endorsement or a compatibility claim.