The VST 3 SDK includes the PluginTestHost application, designed to run on both Mac OS X (Universal Binary) and Windows systems (32-bit and 64-bit). This tool serves as a compact host environment that enables developers to load and test their VST3 plug-ins efficiently.

PluginTestHost simulates audio and event inputs, providing a controlled environment for evaluating plug-in performance. It operates with an ASIO driver to ensure low-latency audio processing, making it an essential utility for plug-in development and debugging.

Additionally, the application features a dedicated test module that assesses compliance with the VST3 standard. This helps developers verify that their plug-ins meet required specifications, facilitating smoother integration with other VST3-compatible software and hardware.