Frequency Calculator
Calculate frequency in hertz from a period in seconds or angular velocity in rad/s.
How it works
- 1Enter a period T in seconds or an angular velocity ω in rad/s — choose the known quantity from the selector.
- 2The calculator applies f = 1/T or f = ω/2π to compute frequency in hertz instantly as you type.
- 3Secondary stats show revolutions per minute (Hz × 60) and the corresponding period (1 ÷ f).
Use cases
- Determine the rotation frequency of a motor shaft given its angular velocity in rad/s.
- Convert a sound wave’s period measured on an oscilloscope into its frequency in hertz.
- Check the spin rate (in rpm) of a centrifuge whose period per revolution is known.
Frequently asked questions
What is the formula for frequency?
Frequency f is the reciprocal of the period T: f = 1/T. If the angular velocity ω is known instead, f = ω/(2π). Both give frequency in hertz (Hz), where 1 Hz = 1 cycle per second.
What is a hertz?
One hertz (Hz) means one complete cycle per second — the SI unit of frequency. For example, mains electricity at 60 Hz completes 60 cycles every second, and a guitar A4 string vibrates at 440 Hz.
Worked example — if T = 0.5 s, what is the frequency?
Apply f = 1/T = 1/0.5 = 2 Hz. Multiplying by 60 gives 120 rpm. Equivalently ω = 2π × 2 ≈ 12.566 rad/s, so entering either value returns 2 Hz.
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