# Open-Cascade-SAS/OCCT

Open CASCADE Technology (OCCT) is an open-source software development platform for 3D CAD, CAM, CAE.

Repository: https://github.com/Open-Cascade-SAS/OCCT
Canonical: https://ross.abutalabs.com/products/occt
Homepage: https://occt3d.com
Language: C++
License: LGPL-2.1
License Family: copyleft
Topics: 3d-cad, cam, cae, cad, occt, opencascade, 3d, occt3d
Last push: 2026-08-25T19:07:21+00:00

## Health v2 (maintenance only)
Score: 94/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 83, longevity 100
- inputs: {"age_days": 2361, "days_push": 8, "days_rel": 34, "gap_med": 69.5, "n_releases_24m": 7}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2800, forks 663 (observed 2026-08-28T04:07:22.530829+00:00)

## What it is
Open CASCADE Technology (OCCT) is an open-source C++ development platform for 3D surface and solid modeling, CAD data exchange, and visualization. It serves as the geometric modeling kernel for building CAD, CAM, and CAE applications.

## Use cases
- build a 3D CAD application
- convert STEP and IGES CAD files between formats
- perform boolean operations on 3D solid models
- create NURBS surfaces and B-Rep geometry programmatically
- render and visualize 3D models in a desktop app
- mesh 3D solids for finite element simulation
- develop CAM toolpath software
- embed a 3D viewer in a web application

## When to choose
- you need a full-featured open-source geometric modeling kernel
- your application requires precise B-Rep solid and surface modeling
- you need robust CAD data exchange (STEP, IGES, BREP)
- you are building cross-platform C++ engineering software
- you want LGPL licensing with a commercial license option

## When to avoid
- you only need lightweight 3D rendering without precise geometry
- you want a simple game-engine-style scene graph
- your team cannot handle a large, complex C++ API
- you need a small dependency footprint

## Facets
- artifact type: library
- maturity: stable
- function: graphics, simulation, sdk, image-processing
- domain: computer-vision, graphics, simulation, developer-tools, cross-platform
- platform: cpp, cross-platform, windows
- tags: 3d-modeling, cad-kernel, cam, cae, geometry-kernel, brep, data-exchange, visualization, c-plus-plus, linux, macos

## Member repositories
- Open-Cascade-SAS/OCCT (main) score 94

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:22.530829+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T08:14:35.562903+00:00, confidence not recorded.
  - readme: https://github.com/Open-Cascade-SAS/OCCT (fetched 2026-08-28T04:07:22.530829+00:00, sha 9495eb0f06bb)
  - homepage: https://occt3d.com (fetched 2026-08-29T09:54:52.259607+00:00, sha f1ddfae9ae4a)
- Data as of 2026-08-30T08:39:29.467469+00:00.