# Pendulum Calculator (Frequency & Period)

Enter the acceleration due to gravity and the length of a pendulum to calculate the pendulum period and frequency. On earth the acceleration due to gravity is always approximately 9.81 m/s^2.

## Pendulum Calculator

The following two formulas are used to calculate the period and frequency of a simple pendulum. In this case, a simple pendulum is described as having no other external forces acting on it. This includes air resistance.

T = 2π * √(L/g)

• Where T is the period (seconds)
• L is the length
• g is the acceleration due to gravity

f = 1/T = 1/2π * √(g/L)

• Where f is the frequency
• L and g are length and acceleration as before