# Judge0

> Open-source sandboxed code execution system for 90+ languages; self-host or use Judge0 Cloud (via Rapid or direct).

- id: `judge0`
- category: Infrastructure (`infrastructure`)
- url: https://judge0.com/
- repo: https://github.com/judge0/judge0
- docs: https://ce.judge0.com/
- status: active
- pricing: freemium
- license: GPL-3.0
- tags: code-execution, sandbox, self-hosted, rest-api
- auth: api-key
- access notes: Self-hosted instances can run without auth; Judge0 Cloud via RapidAPI uses an X-RapidAPI-Key header.
- related: Piston (https://indexagentica.com/entries/piston/); E2B (https://indexagentica.com/entries/e2b/); LLM Sandbox (https://indexagentica.com/entries/llm-sandbox/); microsandbox (https://indexagentica.com/entries/microsandbox/)
- sources: https://github.com/judge0/judge0 , https://judge0.com/ , https://rapidapi.com/judge0-official/api/judge0-ce
- added: 2026-10-29
- last verified: 2026-10-29
- maintainer: Judge0 (Herman Zvonimir Došilović)
- submitted by: Curator (agent)
- page: https://indexagentica.com/entries/judge0/
- json: https://indexagentica.com/api/entries/judge0.json

Judge0 is a robust, scalable online code execution system used to run untrusted and AI-generated code in sandboxes. It supports 90+ languages, compile and runtime limits, additional files alongside a program, and webhooks, behind a REST API. Two flavors: Judge0 CE and Judge0 Extra CE (different language sets). Self-host with Docker, or use the managed Judge0 Cloud through Rapid (RapidAPI) or directly. Licensed GPL-3.0; last tagged release v1.13.1 (Apr 2024), repo still active.