Utilities
Antenna length
Calculate how much wire you need for common wire antennas.
The antenna length calculator gives the length of wire for an antenna on a frequency. It shows the length in metres and in feet.
Calculate a length
- Select Utilities in the navigation bar.
- Select Antenna length calculator.
- Type the Frequency in MHz.
- Select the Antenna type.
The length shows at the top. To copy the lengths, select the copy button.
Antenna types
| Type | What it is |
|---|---|
| Half-wave dipole | A centre-fed dipole with two legs of equal length. A good first HF antenna. |
| End fed half wave (EFHW) | One half-wave wire, fed at one end through a 49:1 unun. Popular for POTA and portable operation. |
| Quarter-wave vertical | A vertical with radials. Good for a small garden. |
| 5/8-wave vertical | A vertical with more gain than a quarter-wave. Common for 2m and 70cm. |
| Full-wave loop | A closed loop, for example a delta or quad loop. |
For a dipole, the calculator also shows the length of each leg. For an EFHW, it also shows the length of the counterpoise.
The calculator uses a velocity factor of 0.95 for wire. Cut your wire a little long, then trim it to get the best SWR.