Doxygen vs Redocly

Doxygen is a free documentation generator that turns source-code comments into reference material, parsing items such as classes, functions and variables. It supports C/C++, Lex, Java, Python, VHDL, PHP IDL, C#, Fortran, Objective-C 2.0 and some D sources. Output can be generated as HTML, PDF through LaTeX, Word through RTF or structured XML for external tools. Graphviz’s dot tool can add include-dependency, collaboration, call, directory-structure and class-hierarchy diagrams. Doxywizard provides a graphical interface for editing settings and running the generator on Windows, Linux and macOS; Doxygen also works on many Unix flavors. It supports HTML Help, docsets, Qt-Help and Eclipse Help, with more than 100 configurable options. The tool runs without registration and does not collect personal or usage data. It is self-hosted and licensed under the GNU General Public License, without express or implied warranty. Help is listed through Stack Overflow and the doxygen users mailing list; commercial feature and bug-fix support has limited capacity.

Redocly is an API documentation and governance suite for teams creating, maintaining, and monitoring API experiences. Redoc generates reference documentation from OpenAPI definitions, with automatic code samples, mock servers, and interactive testing through Replay. Reunite supports collaborative editing, visual reviews, remote content, and deployment previews with an audit trail; it connects to GitHub, GitLab, Azure DevOps, or Redocly’s native Git solution. The open-source CLI validates, lints, and bundles OpenAPI definitions, while the VS Code extension helps write and maintain them and flags definition errors. Reef provides a searchable internal API catalog with metadata, scorecards, and discovery features. Respect monitors APIs against an OpenAPI specification and can send alerts through Slack or email. Redocly lists web, API, and extension platforms, custom domains, and content analytics. It says data is encrypted in transit and at rest and reports a completed SOC 2 Type II audit. Pro costs $10.00 per seat/month, billed monthly, and includes one project and 100 pages. API docs can be launched for free, and the full suite has a 30-day trial.