What does AWG stand for?

AWG stands for American Wire Gauge. It's a standardized system for wire diameter used primarily in the US and Canada. The system dates to 1857 and is based on the number of drawing operations to produce a given wire diameter.

Why do bigger AWG numbers mean thinner wire?

The gauge number corresponds to the number of times the wire is drawn through reducing dies. More drawing passes produce thinner wire. AWG 0000 (4/0) is the thickest standard size at ~11.7 mm, while AWG 40 is hair-thin at ~0.08 mm.

What is 0000 or 4/0 gauge?

Gauges below 1 are expressed as 0, 00 (2/0), 000 (3/0), and 0000 (4/0). In the formula, these correspond to AWG 0, -1, -2, and -3. They are large-diameter wires used for high-amperage applications like battery cables and service entrance conductors.

How do I choose the right wire gauge?

It depends on the current (amps), wire length, and acceptable voltage drop. The National Electrical Code (NEC) provides ampacity tables. As a rule of thumb: 14 AWG for 15A, 12 AWG for 20A, 10 AWG for 30A circuits.

What is the metric equivalent of AWG?

The metric system uses cross-sectional area in mm² directly. AWG 12 ≈ 3.31 mm², AWG 10 ≈ 5.26 mm², AWG 8 ≈ 8.37 mm². IEC 60228 defines standard metric wire sizes like 1.5, 2.5, 4, 6, 10, 16 mm².

Does this work for aluminum wire?

The diameter and area are the same regardless of material. However, resistance differs: aluminum has about 1.6× the resistance of copper. Aluminum wire requires a larger gauge for the same ampacity.

Wire Gauge Converter

Convert AWG wire gauge to diameter in mm and inches, cross-sectional area in mm², and resistance per meter. Covers 0000 to 40 AWG.

AWG Gauge

Material

Wire Length (ft)

System Voltage (V)

Load Current (A)

Diameter

2.053 mm

0.0808 in

Cross-Section Area

3.309 mm²

Conductor cross-section

Resistance per 1000 ft

1.588 Ω

Round-trip 100 ft: 0.3176 Ω

Max Ampacity

20 A

Load within NEC rating

Voltage Drop

5.0816 V

4.23% — NEC recommends below 3%

Weight per Foot

0.0371 lb/ft

Total 100 ft: 3.71 lb

Voltage Drop (4.23%)

NEC 3% limit shown at 30%

Load vs Ampacity (16A / 20A)

AWG Reference Table

AWG	Diam (mm)	Area (mm²)	Cu Ω/1000ft	Al Ω/1000ft	Cu Amp (A)	Al Amp (A)
0	8.252	53.48	0.0983	0.16	150	120
2	6.544	33.63	0.1563	0.254	115	90
4	5.189	21.15	0.2485	0.403	85	65
6	4.115	13.3	0.3951	0.641	65	50
8	3.264	8.367	0.6282	1.02	40	30
10	2.588	5.261	0.9989	1.62	30	25
12	2.053	3.309	1.588	2.575	20	15
14	1.628	2.082	2.525	4.096	15	13
16	1.291	1.309	4.016	6.514	13	10
18	1.024	0.823	6.385	10.35	10	7
20	0.812	0.518	10.15	16.46	5	3
22	0.644	0.326	16.14	26.17	3	2
24	0.511	0.205	25.67	41.6	2	1

Planning notes, formulas, and examples

About the Wire Gauge Converter

The Wire Gauge Converter translates American Wire Gauge (AWG) numbers into physical dimensions: diameter in millimeters and inches, cross-sectional area in mm², and resistance per meter for copper wire. It covers the full AWG range from 0000 (4/0) through 40.

American Wire Gauge is the standard system for measuring wire diameter in the US and Canada. The gauge number is inversely related to diameter — smaller numbers mean thicker wire. AWG uses a logarithmic scale based on the formula d(mm) = 0.127 × 92^((36-AWG)/39), which means every 6 gauge steps roughly doubles the diameter.

Electricians, engineers, audio technicians, and hobbyists need quick access to wire specifications for calculating ampacity, voltage drop, and selecting proper wire for installations. It shows all essential dimensions from a single AWG input.

When This Page Helps

Selecting the right wire gauge is critical for safety and performance. Too thin a wire causes excessive heat and fire risk. This converter gives you all the specs from diameter to resistance in one place.

How to Use the Inputs

Enter the AWG gauge number (0–40, or use negative numbers for 00, 000, 0000).
View the wire diameter in mm and inches.
Check the cross-sectional area in mm² and circular mils.
See the resistance per meter and per foot for copper wire.
Use the ampacity guideline for common applications.

Formula used

d(mm) = 0.127 × 92^((36 - AWG) / 39)
d(in) = d(mm) / 25.4
Area(mm²) = π × (d/2)²
Resistance(Ω/m) = ρ / Area, where ρ(copper) = 1.724 × 10⁻⁸ Ω·m

Example Calculation

Result: 2.053 mm diameter / 3.31 mm² area

AWG 12: d = 0.127 × 92^((36-12)/39) = 2.053 mm. Area = π × (1.0265)² = 3.31 mm². Resistance = 5.21 mΩ/m. This is the standard gauge for 20A household circuits in the US.

Tips & Best Practices

AWG 14 (20A) and AWG 12 (20A with longer runs) are the most common residential wiring gauges.
Every 3 AWG steps doubles the cross-sectional area and halves the resistance.
Every 6 AWG steps doubles the diameter.
For speaker wire, AWG 16 is fine for short runs; use AWG 12 for runs over 50 feet.
Stranded wire has a slightly larger overall diameter than solid wire of the same AWG.

The AWG System

The American Wire Gauge system defines wire sizes from 0000 (4/0, ~11.7 mm diameter) to 40 (~0.08 mm). It was standardized in 1857 and remains the dominant wire sizing system in North America. The logarithmic scale means each 3 gauge steps halves the area and each 6 gauge steps halves the diameter.

Wire Selection for Common Applications

Residential circuits use AWG 14 (15A), 12 (20A), or 10 (30A). Automotive wiring ranges from AWG 18 for signals to AWG 4 for battery cables. Audio speaker wire typically uses AWG 16 for short runs and AWG 12 for long runs or high power.

Metric vs. AWG

Outside North America, wire is specified by cross-sectional area in mm². Common metric sizes are 1.5, 2.5, 4, 6, 10, and 16 mm². There is no exact AWG equivalent for each metric size, so conversions are approximate.

Sources & Methodology

Last updated: February 8, 2026

Frequently Asked Questions

AWG stands for American Wire Gauge. It's a standardized system for wire diameter used primarily in the US and Canada. The system dates to 1857 and is based on the number of drawing operations to produce a given wire diameter.