T = 2π·√(L / g) f = 1 / T · L = g·(T / 2π)²

Pendulum Period: Swing time of a simple pendulum — independent of mass. This free calculator solves for Period, frequency, length, gravity and shows every step.

The physics

For small swings, a simple pendulum's period depends only on its length and gravity — remarkably, not on its mass or (for small angles) its amplitude. That reliability is what made pendulums the heart of accurate clocks for centuries.

Worked example

L = 1.0 m on Earth. T = 2π·√(1 / 9.81) = 2.01 s; f = 1/2.01 = 0.50 Hz.

Common uses

Pendulum clocks, metronomes, seismometers, measuring g, and the foundations of simple harmonic motion.

Frequently asked questions

What is the formula for Pendulum Period?

Pendulum Period uses the formula T = 2π·√(L / g). Swing time of a simple pendulum — independent of mass.

How do you calculate Pendulum Period?

Choose which variable to solve for, enter the values you know (in any supported unit), and the calculator substitutes them into T = 2π·√(L / g) and shows every step of the working. It can solve for Period, frequency, length, gravity.

Is the Pendulum Period calculator free to use?

Yes — every Physics Fundamentals calculator is completely free, with no login, no ads and no usage limits.