Frequency to Wavelength Calculator (Sound)
Quick answer: Enter frequency in Hz. Get wavelength in meters, feet, and inches. Plus 1/4 and 1/2 wave for room treatment.
Calculate the wavelength of any audio frequency. Used by acousticians for room treatment (1/4 wave standing waves), live audio engineers (comb filtering distances), and audio designers (speaker placement, port tuning). Adjustable for temperature and medium.
Advertisement
Last reviewed: April 2026Report an error
Wavelength
0.343 m / 1.127 ft
At 1000 Hz in air (343.4 m/s): wavelength is 0.343 m (1.127 ft / 13.5 in). Quarter wave: 0.086 m. Half wave: 0.172 m.
Wavelength (m)
0.343
Wavelength (ft)
1.127
Quarter Wave
0.086 m
Half Wave
0.172 m
Advertisement
The Formula
λ = c / f ; c_air = 331.4 + 0.6 × T(°C) ; c_water = 1480 m/s
- λ = Wavelength (meters)
- c = Speed of sound in the medium (m/s)
- f = Frequency (Hz)
- T = Temperature (°C, for air only)
How to Use This Wavelength Calculator
- 1Enter the frequency in Hz.
- 2Optionally adjust temperature (default 20°C).
- 3Pick medium (air default, or water for underwater calcs).
- 4Read wavelength in metric and imperial, plus 1/4 and 1/2 wave values.
Frequently Asked Questions
- It determines how sound interacts with rooms and objects. Bass frequencies (20-100 Hz) have wavelengths 3-17 meters — they pass around walls and through gaps. Treble (10kHz) has 3.4 cm wavelength — easily reflected or absorbed by small objects.
- Quarter-wavelength is the standard for resonator absorbers, port tuning in speakers, and modal placement. A 1/4 wave from a wall causes a pressure null where modes can be placed for problem frequencies.
- Speed of sound varies with temperature: 343 m/s at 20°C, 331 m/s at 0°C. A 20°C swing changes wavelength by 4% — relevant for tight-tolerance acoustics or outdoor work in changing conditions.
- When two speakers are at different distances from a listener, sound arrives with a phase difference. At specific frequencies (where the path difference = ½ wavelength), they cancel. Wavelength tells you which frequencies will cancel for a given path difference.
- Frequency × wavelength = speed of sound (constant). Memorize wavelengths: 100 Hz ≈ 11 ft. 1 kHz ≈ 1.1 ft. 10 kHz ≈ 1.3 in. Half it for half-wave, quarter it for quarter-wave.
Advertisement
Related Calculators
</> Embed this calculator on your website
<iframe src="https://calqpro.com/calculators/frequency-to-wavelength-calculator" width="100%" height="600" frameborder="0" title="CalQpro Calculator" loading="lazy"></iframe> <p>Powered by <a href="https://calqpro.com">CalQpro</a></p>
Advertisement