Vibration Analysis Calculator

Analyze single-degree-of-freedom vibration systems. Calculate natural frequency, damping ratio, transmissibility, and amplitude magnification.

Spring Stiffness (k)

lb/in

Supported Weight

Damping Coefficient (c)

lb·s/in

Excitation Frequency

Tab to move between fields

Natural Frequency

31.29 Hz

Transmissibility

8.11

Amplitude Magnification

8.07

Damping Ratio (ζ)0.05

Frequency Ratio (r)0.96

How to Use This Calculator

Enter the Spring Stiffness (k) in lb/in — for isolator pads or mounts, the stiffness is listed in the product datasheet. Add values in parallel.
Enter the Supported Weight in lb — the total weight of the equipment or vibrating mass.
Enter the Damping Coefficient (c) in lb·s/in — for steel structures ≈ 1–5% critical damping; rubber mounts ≈ 5–15%.
Enter the Excitation Frequency in Hz — for rotating machinery use f = RPM / 60.
Review the Natural Frequency in Hz — the excitation frequency should not be within 20% of the natural frequency to avoid resonance.
Check Transmissibility — a value below 1.0 means isolation is effective; above 1.0 means vibration is being amplified.

How the result changes with Supported Weight

Supported Weight	Natural Frequency	Transmissibility	Amplitude Magnification
10,000	0.99 Hz	0	0
35,000	0.53 Hz	0	0
65,000	0.39 Hz	0	0
90,000	0.33 Hz	0	0

Spring Stiffness (k): Total spring stiffness of the support system. For multiple springs in parallel, add stiffness values.
Supported Weight: Weight of the vibrating mass (equipment, rotor, etc.). Converted internally to mass using g = 386.4 in/s².
Damping Coefficient (c): Viscous damping coefficient. Steel structures ≈ 1-5% critical; rubber mounts ≈ 5-15% critical.
Excitation Frequency: Frequency of the forcing vibration. For rotating machinery: f = RPM/60.

Identify Input Parameters
4 parameters
Spring Stiffness (k) = 1000, Supported Weight = 10, Damping Coefficient (c) = 0.5, Excitation Frequency = 30 = 4 input(s) provided
Calculate Natural Frequency
Natural Frequency
31.29 = 31.29
Calculate Transmissibility
Transmissibility
8.105 = 8.105
Calculate Amplitude Magnification
Amplitude Magnification
8.069 = 8.069
Calculate Damping Ratio
Damping Ratio
0.0491 = 0.0491
Calculate Frequency Ratio
Frequency Ratio = r
0.959 = 0.959