KELLER Pressure is one of the world‘s leading manufacturers of piezoresistive pressure sensors and transmitters. Founded in 1974 by Hannes W. Keller, the inventor of the integrated silicon measuring cell, the company remains a wholly family-owned business. Headquartered in Winterthur, Switzerland, KELLER controls its entire value chain—from producing individual silicon components to the final calibration of finished instruments—in its own facilities. This vertical integration ensures that every product carrying the KELLER name is truly “Made in Switzerland” and meets the highest standards of accuracy and reliability.

The KELLER product portfolio includes piezoresistive pressure transducers and transmitters, OEM pressure sensors, digital pressure gauges, submersible level probes, autonomous data loggers, and precision pressure calibrators. With a pressure range spanning 5 mbar to 2000 bar and more than 500 standard products, KELLER also develops custom solutions for specialized industrial, OEM, and research applications. The company operates 14 subsidiaries worldwide, employs approximately 500 people from over 20 countries, and holds ISO 9001 certification. Its sensors are trusted in industries ranging from aerospace and automotive to water management and laboratory metrology, where consistent, traceable pressure measurement is critical.