KaiZen OpenAPI Editor is RepreZen's free, open-source OpenAPI editor for Eclipse. KaiZen Editor supports the current OpenAPI 3.0 description language and the older OpenAPI 2.0 (f.k.a. the Swagger specification). It includes essential editing features including syntax highlighting, real-time validation, code assist, quick outline and hyperlink navigation.
RepreZen API Studio is a complete Eclipse-based OpenAPI modeling environment with powerful features to enable full-lifecycle REST API design, documentation, and development. API Studio uses KaiZen Editor as a core component, and adds live views, mocking, code generation, and more. API Studio is available with flexible subscription plans for individuals and teams.
Here's a feature comparison:
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Installation Options | ||
Install from Eclipse Marketplace into Eclipse IDE (Oxygen or later) | ✔ | ✔ |
 Install as a self-contained desktop application | ✔ | |
API Modeling Languages | ||
| OpenAPI 2.0 (f.k.a. Swagger specification) | ✔ | ✔ |
OpenAPI 3.0 | ✔ | ✔ |
| RAPID-ML | ✔ | |
API Specification Editing | ||
Code assist for keywords and enum values | ✔ | ✔ |
Code assist with customizable, context-sensitive code templates | ✔ | ✔ |
| Code assist for reference properties | ✔ | ✔ |
Code Folding | ✔ | ✔ |
| Outline View and Quick Outline navigation | ✔ | ✔ |
| Hyperlink "go to definition" navigation | ✔ | ✔ |
Toggle word wrap, line numbers, non-printing characters | ✔ | ✔ |
Find and replace with regular expression support | ✔ | ✔ |
Syntax Highlighting | ✔ | ✔ |
| Built-in, customizable light and dark color themes | ✔ | |
| Built-in scope highlighting with light and dark themes | ✔ | |
API Validation and Testing | ||
Real-time validation with error and warning markers, quick fixes, configurable Problems view | ✔ | ✔ |
Keyword and value validation | ✔ | ✔ |
Reference property validation | ✔ | ✔ |
| Embedded example validation against specified schema | ✔ | |
 Integrated API Mock Service | ✔ | |
Multi-File Support | ||
 Reference property code assist with scope cycling | ✔ | ✔ |
 Quick outline view with scope cycling | ✔ | ✔ |
| Documentation view auto-adapts to component files | ✔ | |
 Generate a single OpenAPI file from a multi-file project | ✔ | |
API Documentation and Publishing | ||
 Documentation live view with scroll sync and embedded navigation controls | ✔ | |
 Diagram live view | ✔ | |
 Swagger UI live view | ✔ | |
 API Docs for Confluence BETA | ✔ | |
Code Generation | ||
| Swagger Codegen | ✔ | |
| OpenAPI Generator | ✔ | |
| Documentation, Diagram and Swagger UI GenTemplates | ✔ | |
| Custom code generation | ✔ | |
| Maven & Gradle Integration | ✔ | |
| Execute codegen from IDE, command line, or CI/CD | ✔ | |
| Convenient YAML-based configuration | ✔ | |
Licensing & Support | ||
 Licensing model | Free, Open Source | Subscription, Open Core |
License | Eclipse Public License 1.0 | RepreZen License Agreement |
Free community support on GitHub | ✔ | ✔ |
| Priority technical support from RepreZen | ✔ | |
| Available enterprise support plans | ✔ |
Ready to Get Started?
If you like KaiZen OpenAPI Editor, you'll be amazed at what you can do with RepreZen API Studio.
Check out our individual plans and pricing, upgrade to API Studio, and start building world-class APIs today!