3X-UI is the most popular open-source Xray management panel, providing a full-featured web interface for deploying and monitoring proxy and VPN protocols on Linux servers. The Go backend manages Xray-core instances supporting VLESS, VMess, Trojan, Shadowsocks, WireGuard, Hysteria2, HTTP, SOCKS, Dokodemo-door, and TUN inbounds across TCP, mKCP, WebSocket, gRPC, HTTPUpgrade, and XHTTP transports secured with TLS, XTLS Vision, and REALITY. The Clients page tracks each user with individual traffic quotas, expiration dates, concurrent connection limits, and live online status indicators, while one-click share links, QR codes, and a built-in subscription server distribute configurations in multiple output formats. The multi-node architecture manages and scales deployments across multiple servers from a single panel instance. The Panel Settings page configures listen address, port, URI path, session duration, trusted proxy CIDRs, authentication, and Telegram bot integration for remote monitoring and management alerts. Outbound routing supports WARP, NordVPN, custom rules, load balancers, and proxy chaining. Xray Configs provides template-level control over the core configuration, while the API Docs page exposes a complete RESTful API with in-panel Swagger documentation. Data persists in SQLite by default or PostgreSQL for larger deployments, with database export and import from the panel. Fail2ban integration enforces per-client IP limits. On RepoCloud, deploy 3X-UI on a dedicated VPS with Docker, root SSH access, and complete control over your proxy infrastructure, all under the GPL-3.0 license.