Standing Wave and Harmonics Calculator
Resonant frequency of a string or open pipe at a chosen harmonic, and the closed-pipe frequency alongside.
Results
Frequency
263.846
Hz
Frequency
263.846
Hz
Wavelength
1.30000
m
Frequency
131.923
Hz
Nodes
2
What this tool does
A string fixed at both ends, or a pipe open at both ends, fits a whole number of half-wavelengths, so the harmonics come out as simple multiples of the fundamental — which is what makes them sound musical. A pipe closed at one end fits only odd quarter-wavelengths and sounds an octave lower for the same length, which is the fourth result.
Formula
f = n × v ÷ (2L) (string or open pipe)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
l | Length | m |
v | Wave speed | m/s |
n | Harmonic number | — |
F | Frequency | Hz |
F1 | Frequency | Hz |
WL | Wavelength | m |
FC | Frequency | Hz |
ND | Nodes | — |
Worked example
- Length0.65 m
- Wave speed343 m/s
- Harmonic number1
- Frequency263.846 Hz
- Frequency263.846 Hz
- Wavelength1.30000 m
- Frequency131.923 Hz
- Nodes2
Limitations
- The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.
- The default values are typical reference figures, not measurements of your situation. Replace them with your own data whenever you have it.