Science Calculators

Pendulum Period Calculator

Enter a pendulum's length to calculate its period (time for one full swing) and frequency.

2.006s
period (one full swing)
0.498 Hz
frequency

Uses the small-angle simple pendulum formula T = 2π√(L/g) with standard gravity (9.81 m/s²) — accurate for swings under about 15-20°. A 1-meter pendulum has a period of roughly 2 seconds, the basis of the historical "seconds pendulum."

How to use this tool

  1. 1Enter the pendulum length in meters.
  2. 2See the calculated period and frequency.

Frequently asked questions

Does the pendulum's mass or swing angle matter?+

Mass doesn't affect the period at all. Swing angle only matters for large angles — this formula assumes a small-angle swing (roughly under 15-20°), the standard simple pendulum approximation.