Fluctus is a free 3-operator FM synthesizer designed to deliver a powerful range of sounds through a simple and streamlined interface. It combines ease of use with flexibility, allowing users to explore various sonic textures without overwhelming complexity. The plugin features three operators with adjustable brightness controls, soft and hard saturation options, a multi-mode filter, as well as built-in ping-pong delay and phaser effects, all accessible on a single scalable page.

With over 60 factory patches included, Fluctus offers a broad palette of sounds that can be easily browsed and customized. The user interface scales smoothly from 100% to 200%, enhancing workflow on different screen sizes. It fully supports the modern CLAP plugin API, enabling advanced modulation capabilities and seamless integration with compatible hosts. Additionally, the plugin is available in both 32-bit and 64-bit versions for Windows, ensuring compatibility across a wide range of systems.

Fluctus is confirmed to work in popular digital audio workstations such as Bitwig Studio 4.3 and FL Studio 9 or newer, with native support for features like polyphonic modulation and slide/glide notes. The plugin operates without any copy protection or DRM, providing a hassle-free user experience. This makes Fluctus an excellent choice for musicians and producers seeking a straightforward yet powerful FM synthesizer.