NumberCals

Pendulum Period Calculator

Calculate the period of a simple pendulum (small-angle approximation).

About this calculator

The Pendulum Period Calculator on NumberCals is a free, mobile-friendly tool for anyone needing to calculate the period of a simple pendulum (small-angle approximation). Enter your values in the form below and the result is computed instantly — no sign-up, no installation, no waiting.

Formula used

T = 2π·√(L/g)

What you'll need

  • Length (m) (e.g. 1)
  • Gravity (m/s², default 9.81) (e.g. 9.81)

What you'll get

  • Period T (s)
  • Frequency (Hz)
Formula
T = 2π·√(L/g)

Frequently Asked Questions

Why doesn't mass appear? +

Because for a simple pendulum (small angle, point mass on a massless rod), period depends only on length and gravity — not on mass.

Why 'small-angle'? +

For angles below ~15°, the period is essentially constant. At larger angles, the period grows slightly with amplitude.

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