---
title: rCTF
description: An open-source platform for hosting capture-the-flag competitions.
---

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rCTF is an open-source platform for hosting capture-the-flag competitions. It is developed and maintained by the [OtterSec](https://osec.io) team and has supported public events with thousands of teams.

To view a live demo, visit [demo.rctf.osec.io](https://demo.rctf.osec.io/).

::::card-grid
:::card[Installation]{href=/installation}
Install rCTF with the Docker setup script, or follow the manual setup when you need more control.
:::
:::card[Configuration]{href=/configuration}
Find the available config options and environment overrides, with defaults and working examples.
:::
:::card[Providers]{href=/providers}
Use providers to choose how rCTF sends email, stores uploads, scores challenges, and connects to event services.
:::
:::card[Administration]{href=/admin}
Set admin permissions, manage challenges and teams, review submissions, and change event settings.
:::
:::card[API reference]{href=/api}
Build against the v1 and v2 APIs with typed routes, authentication rules, response formats, and rate limits.
:::
:::card[Theming]{href=/theming}
Customize the web app through its Radix colors, category styles, and reusable Svelte components.
:::
::::