The American Wire Gauge (AWG) is a standardized system used in North America to measure the diameter of solid, non-ferrous electrical wires. In this system, a higher AWG number indicates a smaller wire diameter and thickness.
For example, 24 AWG wire is much thinner than 12 AWG wire.
AWG is a logarithmic scale that has been in use since 1857. It ranges from very thick 0000 (4/0) wire to extremely fine 40 gauge wire. Specific wire sizes are selected based on current capacity (amperage), voltage drop, and application type (power vs. data) to prevent overheating and ensure proper signal performance.
Key Concepts
Inverse Relationship
- Higher AWG number = smaller wire diameter
- Lower AWG number = thicker wire
Logarithmic Scale
- Every 3-gauge decrease roughly doubles the wire’s cross-sectional area
- Every 6-gauge decrease roughly doubles the wire’s diameter
Applications
- Electrical wiring: Focused on power delivery and heat management
- Data cables: Focused on signal integrity, flexibility, and distance
How AWG Works: General Rules
Power Applications
Thicker wires (lower AWG numbers such as 10, 12, or 14) can carry more current with less electrical resistance. These are essential for high-power appliances such as:
- Dryers
- Ovens
- HVAC systems
Using the correct AWG size helps prevent overheating and fire hazards.
Data & Signal Applications
Thinner wires (higher AWG numbers such as 24, 26, or 28) are commonly used for:
- Ethernet cables
- Audio cables
- Low-voltage signal wiring
These wires are more flexible and suitable for low-current applications. However, thicker wires may be preferred for longer cable runs or Power over Ethernet (PoE) to reduce voltage drop.
