FAST-Calib is a ROS-based application for LiDAR-camera extrinsic calibration that uses a target-based approach with ArUco markers and circular holes. The system processes synchronized camera images and LiDAR point clouds to detect calibration target features in both modalities, then computes the extrinsic transformation between sensor frames. It supports both solid-state (Livox) and mechanical (Ouster, Hesai) LiDAR sensors through adaptive preprocessing pipelines. The application includes single-scene calibration for immediate results and multi-scene joint calibration for improved accuracy. Key components include modular LiDAR and camera processing pipelines, geometric validation for target detection, and coordinate transformation utilities.