Frequency to Wavelength Calculator
Convert frequency to wavelength (λ = v/f) for radio, microwave and transmission lines, with velocity factor, half wave and quarter wave antenna lengths.
Runs on your device
Result
Results appear here as you type.
What it does
In free space electromagnetic waves travel at c = 299,792,458 m/s. In coaxial cable or PCB traces they are slower; enter the velocity factor (for example 0.66 for solid polyethylene coax).
How to use it
- Enter the frequency with a prefix (2.4G, 433M, 50).
- Enter the velocity factor (1 for free space).
- Read λ, λ/2, λ/4, period and wave number.
Example
100 MHz in free space: λ ≈ 2.998 m. Select Try an example above to see it.
When it helps
- Cutting dipole and monopole antennas.
- Electromagnetics coursework.
- Checking stub and transmission line lengths.
Questions
Why is my real antenna shorter than λ/2?
End effects mean a practical half wave dipole is about 95% of the free space half wavelength.
What is k?
The wave number, 2π/λ in radians per metre, used in phasor expressions like e^(−jkz).
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