Simple Harmonic Motion Calculator

Use the Simple Harmonic Motion Calculator to compute displacement, velocity, acceleration, period, and frequency for basic SHM, spring-mass systems, and simple pendulums.

950.1K usesUpdated · 2026-04-28Runs locally · zero upload

How to Use Simple Harmonic Motion Calculator

The Simple Harmonic Motion Calculator offers three modes selectable at the top of the tool.

  1. Basic SHM — Enter amplitude A (m), frequency f (Hz), initial phase φ (degrees), and time t (s). The Simple Harmonic Motion Calculator instantly outputs the angular frequency ω, period T, displacement x, velocity v, and acceleration a at the specified instant.
  2. Spring-Mass System — Enter the mass m (kg) and spring constant k (N/m). The Simple Harmonic Motion Calculator applies T = 2π√(m/k) to give the natural period, frequency, and angular frequency.
  3. Simple Pendulum — Enter the pendulum length L (m) and local gravitational acceleration g (m/s²). The Simple Harmonic Motion Calculator uses T = 2π√(L/g) under the small-angle approximation.

Results update live as you change any input. The formula used is shown in the result panel for transparency.

Formula & Theory — Simple Harmonic Motion Calculator

The Simple Harmonic Motion Calculator implements the following equations of motion.

Basic SHM equations:

x(t) = A · cos(ωt + φ)
v(t) = −A · ω · sin(ωt + φ)
a(t) = −ω² · x(t)
ω   = 2πf = 2π / T
Symbol Meaning
A Amplitude — maximum displacement from equilibrium (m)
ω Angular frequency (rad/s)
f Frequency (Hz)
T Period (s)
φ Initial phase angle (degrees)
t Time (s)

Spring-mass natural period:

T = 2π √(m / k)
Symbol Meaning
m Mass (kg)
k Spring stiffness (N/m)

Simple pendulum period (small-angle approximation):

T = 2π √(L / g)
Symbol Meaning
L Effective pendulum length (m)
g Gravitational acceleration (m/s²), default 9.80665

Assumptions

The Simple Harmonic Motion Calculator assumes ideal conditions: no damping, a massless spring, and a point-mass bob for the pendulum. Real systems will deviate based on damping and non-linearities.

Use Cases for Simple Harmonic Motion Calculator

The Simple Harmonic Motion Calculator is widely applicable across physics and engineering:

  • Physics Education — Visualize how changing amplitude, frequency, or phase shifts the motion of a simple harmonic oscillator at any instant in time.
  • Mechanical Engineering — Compute the natural frequency of a spring-mass assembly during initial design to avoid resonance with driving forces.
  • Structural Analysis — Estimate the natural oscillation period of a pendulum-like structural element for seismic and dynamic load analysis.
  • Acoustics — Model a vibrating string or membrane as a Simple Harmonic Motion Calculator input to find the fundamental frequency.
  • Laboratory Experiments — Verify theoretical predictions by comparing the Simple Harmonic Motion Calculator output with measured oscillation data from spring or pendulum experiments.

The Simple Harmonic Motion Calculator saves time on routine SHM computations, letting students and engineers focus on analysis rather than arithmetic.

Frequently asked questions about Simple Harmonic Motion Calculator

What can the Simple Harmonic Motion Calculator compute?

The Simple Harmonic Motion Calculator covers three modes: basic SHM (displacement, velocity, acceleration at time t), spring-mass systems (period via T = 2π√(m/k)), and simple pendulums (period via T = 2π√(L/g)).

What is the formula for displacement in simple harmonic motion?

The Simple Harmonic Motion Calculator uses x(t) = A·cos(ωt + φ), where A is amplitude, ω = 2πf is angular frequency, t is time, and φ is the initial phase angle in degrees.

Does the pendulum mode apply to large angles?

No. The Simple Harmonic Motion Calculator uses the small-angle approximation T = 2π√(L/g), which is accurate for angles below about 15°. For larger angles, a correction factor is needed.

Is my data stored?

No. All calculations happen in your browser; nothing is sent to a server.