Pendulum Period Calculator
Period of a simple pendulum from its length.
Enter your values
Enter the pendulum length in m.
Enter the gravity in m/s².
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Period
- 2.006 s
- Frequency
- 0.498 Hz
- Oscillations per minute
- 29.9
Quick answer
Period T = 2 x pi x sqrt(L/g) for small swing angles.
T = 2 pi sqrt(L/g)
At a glance
| What it does | Period of a simple pendulum from its length. |
|---|---|
| Category | Physics |
| Inputs needed | Pendulum length, Gravity |
| Main output | Period |
| Formula | T = 2 pi sqrt(L/g) |
| Cost | Free — no sign-up, no download |
How to use the Pendulum Period Calculator
- 1Enter the pendulum length from pivot to the centre of the bob.
- 2Adjust gravity if not on Earth.
- 3Read the period, frequency and swings per minute.
Inputs explained
- Pendulum length(m)
- Enter the pendulum length in m.
- Gravity(m/s²)
- Enter the gravity in m/s².
Worked example
Using the values the calculator loads with:
Inputs
- Pendulum length1 m
- Gravity9.81 m/s²
Results
- Period2.006 s
- Frequency0.498 Hz
- Oscillations per minute29.9
Frequently asked questions
Does the mass of the bob matter?
No — the period of a simple pendulum depends only on length and gravity, not mass.
Is this accurate for wide swings?
The small-angle formula is accurate below about 15 degrees; larger swings take slightly longer.
What do I need to enter into the Pendulum Period Calculator?
Just 2 values: pendulum length, gravity. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Pendulum Period Calculator work out the answer?
Period T = 2 x pi x sqrt(L/g) for small swing angles. It applies the formula T = 2 pi sqrt(L/g) and shows the working so you can check each step by hand.
Is the Pendulum Period Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.