Find the small-angle period T = 2π √(L/g) and the frequency of a simple pendulum.
| Period (s) | – |
| Frequency (Hz) | – |
Use this calculator for a simple pendulum on a small swing: period is T = 2π √(L/g) and frequency is 1/T. L is the length to the centre of the bob.
The formula assumes a few degrees of amplitude and no friction. A 1 m pendulum on Earth has T ≈ 2.0 s. Large angles, a physical pendulum, or air drag need a different model.
Length (m): Pivot to the centre of the bob, in metres.
g (m/s²): Local gravity; usually 9.81 m/s² on Earth.
Period (s): Time for one full swing, in seconds.
Frequency (Hz): Oscillations per second, 1/T.
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