Acoustic Tachometer
Estimate RPM from engine sound.
Acoustic Tachometer listens through your iPhone microphone, finds the dominant firing frequency, and estimates RPM for cars, motorcycles, small engines, and rotary engines without attached hardware.
Results depend on microphone placement, background noise, and the selected engine profile. Use a trusted tachometer for final verification.
Measurement
Fast checks without clipping on a sensor.
Pick an engine profile, start listening, and compare RPM confidence, harmonic support, and candidate frequencies while tuning idle or checking repeatability.
Engine profiles
Use firing-pattern presets for common engines and rotary configurations.
Confidence readout
See lock state, prominence, harmonic support, and alternate frequency candidates.
Local sessions
Keep measurements on device for quick comparisons without accounts or tracking.