# Frequency Calculator (f = v/λ)

Calculate frequency from wavelength and wave speed (f = v/λ) or from period (f = 1/T). Results in Hz and kHz with angular frequency.

## What this calculates

Frequency measures how many complete wave cycles pass a point per second, measured in Hertz (Hz). This calculator determines frequency from wavelength and wave speed, or directly from the period. It also provides the angular frequency (ω = 2πf) used in many physics and engineering formulas.

## Inputs

- **Wavelength (λ)** (m) — min 0
- **Wave Speed** (m/s) — min 0 — Sound in air: 343, Light: 3×10⁸
- **Period (optional)** (s) — min 0 — If provided, f = 1/T is used instead

## Outputs

- **Frequency** (Hz) — Cycles per second
- **Frequency** (kHz) — Frequency in kilohertz
- **Angular Frequency** (rad/s) — ω = 2πf
- **Period** (s) — T = 1/f

## Frequently Asked Questions

**Q: What is frequency?**

A: Frequency is the number of complete oscillations or wave cycles that occur per unit of time. The SI unit is Hertz (Hz), where 1 Hz equals one cycle per second. Higher frequency means more rapid oscillation, which for sound means a higher pitch and for light means a shift toward the blue/violet end of the spectrum.

**Q: What is the difference between frequency and period?**

A: Frequency (f) and period (T) are reciprocals of each other: f = 1/T and T = 1/f. Frequency tells you how many cycles happen per second, while period tells you how long one cycle takes. A 100 Hz wave has a period of 0.01 seconds (10 milliseconds).

**Q: What is angular frequency?**

A: Angular frequency (ω = 2πf) measures how quickly the phase of a wave changes, in radians per second. It is widely used in physics and engineering because many formulas become simpler when expressed in terms of ω rather than f. One complete cycle corresponds to 2π radians.

**Q: What frequency range can humans hear?**

A: The human ear can typically detect sound frequencies between about 20 Hz and 20,000 Hz (20 kHz). Frequencies below 20 Hz are called infrasound, and above 20 kHz are ultrasound. Hearing sensitivity decreases with age, particularly at higher frequencies.

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Source: https://vastcalc.com/calculators/physics/frequency
Category: Physics
Last updated: 2026-04-21