⏱️Pendulum Calculator
Find the period, frequency, or length of a simple pendulum using T = 2π√(L/g).
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Free Pendulum Calculator
Curious how long it takes a pendulum to swing back and forth? Our free pendulum calculator finds the period, frequency, or length of a simple pendulum instantly using T = 2π√(L/g). Enter the length and gravity, or work backwards from a known period, and see the result immediately.
Presets for Earth, Moon, and Mars gravity let you quickly compare how a pendulum would behave on different worlds, and a live animated pendulum shows the swing visually as you adjust the values. The calculator also flags when your swing angle is too large for the standard small-angle formula to stay accurate.
Whether you're studying simple harmonic motion or just experimenting with the physics of a swing, this tool gives clear, accurate answers with the working shown. No sign-up, no downloads, no limits. See the About page or the FAQ for more.