Tools · Measurement
Vibration unit converter
Enter one amplitude and a frequency. Get every other unit, for a single-frequency (sinusoidal) vibration.
| Quantity | Peak | RMS | Peak-to-peak |
|---|
Valid for a single-frequency sine (peak = √2 × RMS). A broadband overall value can't be converted between units this way, because each frequency in it scales differently.
The formulas
For a sinusoid at angular frequency ω = 2πf, each integration divides by ω:
v = a / (2πf) d = v / (2πf) = a / (2πf)²
peak = √2 × RMS peak-to-peak = 2 × peak
That's why the same machine looks very different in different units. Acceleration emphasises high frequencies (bearings, gears), displacement emphasises low ones (unbalance on slow machines), and velocity sits in between. That's why velocity is the usual unit for overall severity on most industrial machines.
Conventions: velocity is usually reported as RMS (ISO) or peak (often in the US), displacement as peak-to-peak, and acceleration as peak or RMS. Always check which one your instrument shows. 1 g = 9.80665 m/s².