Judge0 CE

About Judge0 CE

Judge0 CE is an open-source online code execution system accessed through a REST API. It supports compiling and running source code in more than 60 programming languages, including multi-file programs and additional files alongside a user's program, within a sandboxed environment. The API allows configuration of runtime constraints such as CPU and wall-clock time limits, memory limits, stack limits, process/thread limits, file size limits, and network access, along with custom compiler options, command-line arguments, and stdin, and it can compare program output against an expected output.

The system exposes endpoints for creating and retrieving individual submissions as well as batches of submissions, and for querying available languages and execution statuses. It supports optional authentication via an X-Auth-Token header and authorization via an X-Auth-User header, both configurable by the instance administrator. It also provides system information, configuration info, statistics, health check, and worker information endpoints, and supports webhooks for submission callbacks.

It is intended for developers building applications that require online code execution, such as competitive programming platforms, e-learning platforms, candidate assessment and recruitment tools, online code editors, and online IDEs. Judge0 is available as a self-hosted deployment or through a hosted plan on RapidAPI, and it is licensed under the GNU General Public License v3.0. It comes in two flavors, Judge0 CE and Judge0 Extra CE, which differ primarily in supported languages.

Key features

• Sandboxed code compilation and execution in 60+ programming languages
• Compilation and execution of multi-file programs with additional supporting files
• Custom user-defined compiler options, command-line arguments, and time/memory limits
• Detailed execution results with configurable runtime constraints
• Webhooks (HTTP callbacks) for submission results
• Scalable, self-hostable architecture with rich API documentation

Frequently asked questions