Speaker Wire Gauge Calculator
Find the right wire gauge for any speaker run, or plan all your runs at once with the multi-run planner.
Recommended Wire Gauge
18 AWG
For 25ft run with 8Ω speakers at ≤5% loss
Wire Gauge Thickness
All Gauges Compared
| Gauge | Resistance | Power Loss | OK? |
|---|---|---|---|
| 10 AWG | 0.05Ω | 0.62% | |
| 12 AWG | 0.081Ω | 1% | |
| 14 AWG | 0.126Ω | 1.55% | |
| 16 AWG | 0.201Ω | 2.45% | |
| 18 AWGBest | 0.319Ω | 3.84% | |
| 20 AWG | 0.507Ω | 5.97% |
In-Wall Cable Ratings
For any in-wall speaker wire, CL2 is the minimum code requirement. Use CL3 for commercial or runs over 50V.
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Find an InstallerChoosing the Right Speaker Wire Gauge
Speaker wire gauge (AWG) determines how much resistance the cable adds between your amplifier and speakers. Thicker wire (lower AWG) means less resistance and less power loss. The right gauge depends on cable run length, speaker impedance, and acceptable power loss.
For most home theater setups with runs under 50 feet and 8-ohm speakers, 16 AWG works perfectly. Longer runs (50–100 feet) or 4-ohm speakers need 14 or 12 AWG. In-wall installations require CL2 or CL3 rated cable for code compliance.
Use the Multi-Run Planner to plan all speaker runs at once — ideal for surround sound and Atmos layouts. It generates a shopping list with total wire per gauge. Pair with our Amplifier Power Calculator and Conduit Fill Calculator.
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