What Is AWG? Understanding the American Wire Gauge System
When selecting electrical wires or cable assemblies, one of the most common terms you will see is AWG, short for American Wire Gauge.
Understanding AWG is essential for choosing the right wire for electrical performance, safety, and reliability, especially in applications such as wire harnesses, industrial equipment, Ethernet cables, and power systems.
This article explains what AWG is, how it works, and why it matters, in clear and simple terms.
What Does AWG Mean?
AWG (American Wire Gauge) is a standardized system used to define the diameter and thickness of electrical wires.
It is mainly used for copper conductors, aluminum conductors, and solid/ stranded wires. AWG is widely applied in wire harness assemblies, power cables, ethernet, communication cables, automotive, and industrial wiring. Even outside the United States, AWG is commonly referenced in connector datasheets, terminal specifications, and UL-certified cables.
How the AWG Number System Works
One important rule to remember is the smaller the AWG number, the thicker the wire. For example:
• 40 AWG → very thin wire
• 24 AWG → common signal wire
• 18 AWG → power wire
• 10 AWG → heavy-duty power wire
This may feel contradictory, but it is how the system was historically defined.
AWG is a logarithmic system, not a simple step-by-step scale. Every 3 AWG size represents approximately double or half the cross-sectional area. Small changes in AWG can mean large changes in electrical performance. That is why 22 AWG and 20 AWG are not “almost the same”. Thicker wire can carry significantly more current and produce less heat
What Does AWG Affect in Real Applications?
AWG directly or indirectly impacts several key factors:
1.Electrical Resistance
• Thicker wire (lower AWG) → lower resistance
• Lower resistance → less voltage drop and heat
This is critical for long cable runs and power delivery.
2.Current Carrying Capacity (Ampacity)
Wire gauge influences how much current a wire can safely carry. However, AWG alone does not define ampacity. Current rating also depends on insulation material, temperature rating, bundling conditions, and installation environment. That is why professional wire harness design always includes derating rules, not just AWG tables.
3.Heat Generation
Thinner wires heat up faster under load, and excess heat can cause electrical failure and safety risks. This is especially important in power cables and PoE (Power over Ethernet) systems.
4.Mechanical Strength
Lower AWG (thicker wire) provides better crimp strength, higher pull resistance, and improved durability in vibration environments. For industrial and automotive wire harnesses, mechanical reliability is just as important as electrical performance.
AWG and Stranded vs Solid Wire
AWG defines the total cross-sectional area of the conductor, not how the wire is constructed. That means 22 AWG solid wire and 22 AWG stranded wire both have the same copper area, but very different properties. Solid wire is better for fixed installations, lower signal variation, but less flexible. Stranded wire is more flexible, better for movement and vibration, and preferred in wire harness assemblies.
AWG vs Metric Wire Size (mm²)
AWG is not a metric system, so conversions are approximate. When working with global customers, it is important to confirm actual conductor area, check connector and terminal compatibility, and avoid assuming direct equivalence.
Common references:
•24 AWG ≈ 0.20 mm²
•22 AWG ≈ 0.33 mm²
•20 AWG ≈ 0.52 mm²
•18 AWG ≈ 0.82 mm²
Why Understanding AWG Matters in Wire Harness Design
Incorrect wire gauge selection can lead to voltage drop issues, overheating, crimp failures, and compliance rejection (UL / safety audits). In custom wire harness manufacturing, AWG selection must align with connector ratings, terminal specifications, application environment, and regulatory requirements. This is why experienced manufacturers evaluate the full system, not just wire size.
Everbiz Industrial: Supporting the Right AWG Selection
At Everbiz Industrial, we support customers in selecting the correct AWG wire size for their applications, including:
•Industrial wire harnesses
•Ethernet and communication cables
•Power and control assemblies
Our approach focuses on reliability, safety, and long-term performance, not just cost reduction. Contact our team at sales@everbiz.com.tw now
