Wavelength Calculator
Wavelength from frequency and wave speed, including the quarter-wave length.
Results
Wavelength
2.997925
m
Wavelength
299.7925
cm
Length
0.749481
m
Frequency for that wavelength
99.930819
MHz
Speed from that wavelength and frequency
300,000,000.000
m/s
Period — how long one cycle takes
0.000000010000
s
Angular frequency
628,318,530.718
rad/s
Wave number
2.094395
1/m
What this tool does
Wavelength is how far a wave travels during one cycle, so it is the wave speed divided by the frequency. Use 299 792 458 m/s for radio and light, or about 343 m/s for sound in air at room temperature; the quarter wavelength is the figure antenna builders need.
Formula
λ = v ÷ f
Variables
| Symbol | Meaning | Unit |
|---|---|---|
f | Frequency | MHz |
v | Wave speed | m/s |
wl | Wavelength, if you know it | m |
L | Wavelength | m |
LC | Wavelength | cm |
QW | Length | m |
FW | Frequency for that wavelength | MHz |
VW | Speed from that wavelength and frequency | m/s |
PD | Period — how long one cycle takes | s |
AW | Angular frequency | rad/s |
KW | Wave number | 1/m |
Worked example
- Frequency100 MHz
- Wave speed299,792,458 m/s
- Wavelength, if you know it3 m
- Wavelength2.997925 m
- Wavelength299.7925 cm
- Length0.749481 m
- Frequency for that wavelength99.930819 MHz
- Speed from that wavelength and frequency300,000,000.000 m/s
- Period — how long one cycle takes0.000000010000 s
- Angular frequency628,318,530.718 rad/s
- Wave number2.094395 1/m
Limitations
- The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.
- Mixing units is the most common source of error. Convert every input to the units shown next to each field before calculating.