Universal VNA Calibration Modules (uCal) simplify and expedite the calibration process of a Vector Network Analyzer (VNA) by automating the use of calibration standards, reducing human error, and providing accurate results without manual intervention. A uCal contains a set of precisely defined and integrated calibration standards, each standard individually characterized with measurement uncertainty and stored on the uCal’s onboard memory. The uCal is equipped with electronic switches to select and connect the appropriate calibration standard to the VNA, thereby enabling rapid transitions between standards without physically disconnecting or reconnecting cables, reducing the chances of human-induced errors like improper torque or connector wear.