Which Wire for Antenna? Best Choices Explained

Updated 6 November 2026 · Standard formula, shown below

For most DIY antennas, the best wire is plain copper or copper-clad steel (CCS) in the 12–18 AWG range, because it conducts well, resists corrosion, and is easy to solder and string up. For permanent outdoor installations, use tinned copper or copper-clad steel with a UV-resistant jacket; for temporary or indoor antennas, bare or enameled copper works fine. This guide explains the properties that matter, how to choose for your frequency and environment, and common mistakes to avoid.

Why Wire Choice Matters

Antenna wire affects three things: efficiency, durability, and ease of construction. Efficiency is about resistance—losses in the wire convert RF power to heat. For most HF antennas (3–30 MHz), even thin copper wire has losses below 0.1 dB, so thicker wire is not about efficiency but about mechanical strength and bandwidth. Durability matters outdoors: bare copper corrodes, turning green and eventually becoming brittle. Tinned copper resists corrosion, and copper-clad steel (CCS) combines conductivity with tensile strength—it stretches less and survives wind and ice better. For receiving-only antennas, even thin wire like 26 AWG works, but for transmitting, you need enough current-carrying capacity to handle the RF power without overheating—though at typical ham power levels (100 W), even 24 AWG is fine.

How to Choose by Frequency and Type

The frequency determines the wire length, not the thickness. A half-wave dipole for 7 MHz is about 20 m long, while for 2.4 GHz it is about 6 cm. The wire gauge is chosen for mechanical strength and ease of soldering, not for electrical reasons. Here are typical choices:

HF (1–30 MHz): 14–18 AWG copper or CCS. For long wire antennas (e.g., 40 m end-fed), use 14 AWG CCS for strength.
VHF/UHF (30 MHz–3 GHz): 12–16 AWG copper or aluminum tubing for Yagis; for simple dipoles, 16 AWG is plenty.
Indoor antennas: 20–26 AWG enameled copper (magnet wire) is easy to hide and works well for receiving.
Portable antennas: 18–20 AWG stranded copper or CCS—flexible and light.

For wire antennas like dipoles, the length is typically 0.95 × (half-wavelength) to account for the velocity factor and end effects.

Copper vs. Copper-Clad Steel vs. Aluminum

Copper is the best conductor (resistivity 1.724×10�� Ω·m) and easy to solder, but it is soft and expensive. Copper-clad steel has a steel core with a copper coating—it is much stronger, resists stretching, and is cheaper than solid copper. It has slightly higher resistance (about 1.5–2× that of copper), but for antennas that is irrelevant. Aluminum is light and cheap but hard to solder, corrodes quickly, and requires special connectors. For most hobbyists, copper or CCS is the best balance. Stainless steel is strong but has high resistance—only use it for guys, not as the radiating element. Silver-plated copper is used in high-end VHF/UHF antennas because silver has lower resistance, but the difference is negligible at HF.

Common Mistakes and Misconceptions

Using too thin wire for long spans: Thin wire (e.g., 26 AWG) may break under its own weight over a 20 m span. Use at least 18 AWG for outdoor long wires.
Ignoring the insulation: Insulated wire works fine, but the insulation adds a velocity factor (typically 0.95–0.98) that slightly shortens the resonant length. If you cut the wire to the theoretical length, the antenna will be a bit too long; trim it.
Using steel wire for the radiator: Steel has high resistance (about 10× copper), which can cause significant losses, especially on receive. Use copper or CCS.
Not accounting for corrosion: Bare copper outdoors will corrode over time, increasing resistance and eventually breaking. Use tinned copper or CCS.
Thinking thicker is always better: A 6 AWG wire is not 10× better than 16 AWG—it is just heavier and harder to work with. The radiation resistance is what matters, not the wire thickness.

Cost and Availability

Copper wire is available at hardware stores (as THHN building wire) or online. A 100 m spool of 14 AWG copper costs a few tens of dollars. Copper-clad steel is sold by ham radio suppliers, often as “antenna wire� in 14 or 16 AWG. Magnet wire (enameled copper) is cheap at electronics stores. For a typical dipole, you need about 20 m of wire—so the material cost is under $20. For a full HF multiband antenna, you might need 50–100 m, still under $50. Avoid buying “silver-plated� wire unless you need it for a specific high-frequency application; it is much more expensive.

Safety and Installation Tips

When installing an outdoor antenna, always keep it away from power lines—at least twice the length of the antenna plus 3 m. Never work on an antenna during a thunderstorm. Use a strain relief (e.g., an insulator) at each end, and make sure the wire is not under excessive tension. For the feed point, use a proper balun if you are connecting to coax. For end-fed antennas, ensure the feed line is decoupled to avoid RF in the shack. Always ground your antenna system according to local electrical codes—but this is not legal advice, just a general safety reminder. When soldering, use rosin-core solder and a hot iron; avoid acid flux which can corrode the joint.

Frequently Asked Questions

Can I use speaker wire for an antenna? Yes, speaker wire is stranded copper and works fine for indoor or temporary antennas. It is not UV-resistant, so it will degrade outdoors, but for a quick test it is fine.

What is the best wire for a long wire antenna? For a long wire (e.g., 40 m or more), use 14 AWG copper-clad steel. It is strong enough to span long distances without stretching and conducts well.

Does wire thickness affect SWR? Not directly. SWR is determined by the antenna’s impedance match to the feed line. Thicker wire slightly increases bandwidth, but it does not change the resonant frequency much. A thicker wire may make the SWR less sensitive to small length errors.

Can I use aluminum wire for a dipole? Yes, but it is harder to solder and corrodes quickly. You can use mechanical connectors (e.g., split bolts) and coat the joint with silicone grease. For most people, copper is easier.

How do I know what length to cut the wire? For a half-wave dipole, the length in meters is approximately 143 / frequency (MHz). For example, at 7.1 MHz, that’s 143/7.1 ≈ 20.1 m. This is the total length; each leg is half. Then trim to achieve the lowest SWR.

Is insulated wire better than bare wire? Insulated wire is more durable and prevents shorting if it touches something, but it adds a slight velocity factor. Bare wire is lighter and has slightly lower loss, but it must be kept away from conductive objects. Both work well.

Method: the standard formula for this calculation, rounded as each result states. See how the calculators work or report an error.