Engine RPM

This app measures the RPM of an engine by analyzing the sound it makes. It uses advanced auto-correlation signal processing algorithms to measure the pitch of the sound and display the calculated RPM.

This app will not work if the engine sounds are too muffled or unstable or combined with too much other noise. The engine sound must be clear and stable and have a definite pitch. Other extraneous sounds can also prevent the engine sound from being analyzed.

The software is configurable for 2-cycle and 4-cycle engines and includes a generic configuration for unusual cases, such as a reduction gear. The normal RPM range is 400 to 90,000 RPM, although much lower RPMs can be measured using the manual RPM matching option.