Vibration Natural Frequency Calculator
Enter spring stiffness, mass, and optional damping to get the natural and damped frequencies of a single-degree-of-freedom system.
System Parameters
N/m
kg
N·s/m
Results
Angular natural frequency ωn
—
Natural frequency fn
—
Natural period Tn
—
Critical damping cc
—
Damping ratio ζ = c/cc
—
Damped natural frequency fd
—
System Behavior
SDOF Mode Shape: A single-degree-of-freedom system has exactly one mode. The normalized mode shape vector is [1] — the entire mass moves as a single unit. For multi-DOF systems, mode shapes describe the relative displacements of each mass at each natural frequency.
Enter stiffness and mass, then click Calculate.
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Summary
Enter spring stiffness, mass, and optional damping to get the natural and damped frequencies of a single-degree-of-freedom system.
How it works
- Enter the spring stiffness k (N/m) and mass m (kg).
- Optionally enter the damping coefficient c (N·s/m) to compute the damped frequency.
- Click Calculate — the tool applies fn = (1/2π)·√(k/m) for the undamped natural frequency.
- The critical damping coefficient cc = 2·√(k·m) is computed, then ζ = c/cc for the damping ratio.
- Damped natural frequency fd = fn·√(1−ζ²) is shown when ζ < 1 (underdamped system).
- The mode shape panel describes the physical motion type based on your damping ratio.
Use cases
- Mechanical engineers sizing isolators to avoid resonance with equipment.
- Structural analysts checking floor or bridge natural frequencies against operating loads.
- Students verifying vibration textbook problems for SDOF systems.
- Designers comparing undamped and damped responses to choose the right dashpot.
- Quality engineers troubleshooting vibration failures in rotating machinery.
- Educators demonstrating the effect of damping ratio on oscillatory behavior.
Frequently Asked Questions
Last updated: 2026-06-11 ·
Reviewed by Nham Vu