Visual comparison
How AWG wire sizes compare
Common bare-copper AWG conductors shown at proportional thickness.
Wire specimens are drawn at a common length with conductor thickness scaled to nominal bare solid-wire diameter. The comparison preserves the relative diameter differences between the sizes shown; screen dimensions are not physical size.
Instant lookup
Find an AWG wire size
Choose a gauge to see its nominal bare solid-wire dimensions immediately.
AWG measures the conductor. Diameter values do not include insulation or cable jacket thickness.
- Diameter
- 0.08081 in
- Area
- 3.31 mm²
- Circular mils
- 6,530 cmil
- Cu resistance
- 1.588 Ω/kft DC at 20°C
Resistance is calculated from the International Annealed Copper Standard resistivity basis at 20°C and the nominal circular-mil area shown in this chart.
Primary reference
Complete AWG Wire Size Chart
Diameter, area, circular mils, and copper resistance from 4/0 through 40 AWG.
Search a gauge or filter the range. Select rows when you want to compare sizes in the interactive chart.
No AWG sizes match the current filters.
Scroll horizontally to view additional columns and vertically to view additional rows. Column headers remain visible while scrolling.
| Compare | Copy | ||||||
|---|---|---|---|---|---|---|---|
| 4/0 | 0.0490 | 0.4600 | 11.684 | 211,600 | 107.2 | ||
| 3/0 | 0.0618 | 0.4096 | 10.405 | 167,806 | 85.0 | ||
| 2/0 | 0.0779 | 0.3648 | 9.266 | 133,077 | 67.4 | ||
| 1/0 | 0.0983 | 0.3249 | 8.251 | 105,535 | 53.5 | ||
| 1 | 0.124 | 0.2893 | 7.348 | 83,693 | 42.4 | ||
| 2 | 0.156 | 0.2576 | 6.544 | 66,371 | 33.6 | ||
| 3 | 0.197 | 0.2294 | 5.827 | 52,635 | 26.7 | ||
| 4 | 0.248 | 0.2043 | 5.189 | 41,741 | 21.2 | ||
| 5 | 0.313 | 0.1819 | 4.621 | 33,102 | 16.8 | ||
| 6 | 0.395 | 0.1620 | 4.115 | 26,251 | 13.3 | ||
| 7 | 0.498 | 0.1443 | 3.665 | 20,818 | 10.5 | ||
| 8 | 0.628 | 0.1285 | 3.264 | 16,510 | 8.37 | ||
| 9 | 0.792 | 0.1144 | 2.906 | 13,093 | 6.63 | ||
| 10 | 0.999 | 0.1019 | 2.588 | 10,383 | 5.26 | ||
| 11 | 1.260 | 0.09074 | 2.305 | 8,234 | 4.17 | ||
| 12 | 1.588 | 0.08081 | 2.053 | 6,530 | 3.31 | ||
| 13 | 2.003 | 0.07196 | 1.828 | 5,178 | 2.62 | ||
| 14 | 2.525 | 0.06408 | 1.628 | 4,107 | 2.08 | ||
| 15 | 3.184 | 0.05707 | 1.450 | 3,257 | 1.65 | ||
| 16 | 4.015 | 0.05082 | 1.291 | 2,583 | 1.31 | ||
| 17 | 5.063 | 0.04526 | 1.150 | 2,048 | 1.04 | ||
| 18 | 6.385 | 0.04030 | 1.024 | 1,624 | 0.823 | ||
| 19 | 8.051 | 0.03589 | 0.9116 | 1,288 | 0.653 | ||
| 20 | 10.15 | 0.03196 | 0.8118 | 1,022 | 0.518 | ||
| 21 | 12.80 | 0.02846 | 0.7229 | 810 | 0.410 | ||
| 22 | 16.14 | 0.02535 | 0.6438 | 642 | 0.326 | ||
| 23 | 20.36 | 0.02257 | 0.5733 | 509 | 0.258 | ||
| 24 | 25.67 | 0.02010 | 0.5106 | 404 | 0.205 | ||
| 25 | 32.37 | 0.01790 | 0.4547 | 320 | 0.162 | ||
| 26 | 40.81 | 0.01594 | 0.4049 | 254 | 0.129 | ||
| 27 | 51.47 | 0.01420 | 0.3606 | 202 | 0.102 | ||
| 28 | 64.90 | 0.01264 | 0.3211 | 160 | 0.0810 | ||
| 29 | 81.83 | 0.01126 | 0.2859 | 127 | 0.0642 | ||
| 30 | 103.19 | 0.01003 | 0.2546 | 101 | 0.0509 | ||
| 31 | 130.12 | 0.008928 | 0.2268 | 80 | 0.0404 | ||
| 32 | 164.08 | 0.007950 | 0.2019 | 63 | 0.0320 | ||
| 33 | 206.90 | 0.007080 | 0.1798 | 50 | 0.0254 | ||
| 34 | 260.90 | 0.006305 | 0.1601 | 40 | 0.0201 | ||
| 35 | 328.98 | 0.005615 | 0.1426 | 32 | 0.0160 | ||
| 36 | 414.84 | 0.005000 | 0.1270 | 25 | 0.0127 | ||
| 37 | 523.10 | 0.004453 | 0.1131 | 20 | 0.0100 | ||
| 38 | 659.62 | 0.003965 | 0.1007 | 16 | 0.0080 | ||
| 39 | 831.77 | 0.003531 | 0.0897 | 12 | 0.0063 | ||
| 40 | 1048.84 | 0.003145 | 0.0799 | 10 | 0.0050 |
Dimensions describe nominal bare solid round-wire geometry. Copper resistance is a calculated DC reference at 20°C; actual conductor resistance varies with material, temperature, stranding, and manufacturing tolerances. Insulation and cable outside diameter are not included.
Area lookup and table actions
Solid vs. stranded AWG diameter
AWG identifies conductor size, not finished cable outside diameter. The diameter values in this chart represent the nominal geometry of a solid round conductor. A stranded conductor of the same AWG normally has a larger overall conductor diameter because individual strands do not fill a perfect circle, and insulation or jackets add still more outside diameter.
Use manufacturer dimensions for fit. For conduit fill, connectors, glands, terminals, or cable-routing clearances, use the actual insulated conductor or cable outside diameter rather than the bare-solid AWG diameter from this chart.
Metric conversion
AWG ↔ mm² converter
Convert an AWG designation or find the nearest nominal AWG area to a metric target.
AWG to mm²
mm² to nearest AWG
AWG and metric conductor sizes are different sizing systems. A metric size such as 2.5 mm² is not literally an AWG size; the converter identifies the closest nominal AWG area and shows adjacent sizes for context.
Quick reference
Common AWG wire sizes
Frequently referenced conductor sizes at a glance.
- Diameter
- 5.189 mm
- Area
- 21.2 mm²
- Cu @ 20°C
- 0.248 Ω/kft
- Diameter
- 4.115 mm
- Area
- 13.3 mm²
- Cu @ 20°C
- 0.395 Ω/kft
- Diameter
- 3.264 mm
- Area
- 8.37 mm²
- Cu @ 20°C
- 0.628 Ω/kft
- Diameter
- 2.588 mm
- Area
- 5.26 mm²
- Cu @ 20°C
- 0.999 Ω/kft
- Diameter
- 2.053 mm
- Area
- 3.31 mm²
- Cu @ 20°C
- 1.588 Ω/kft
- Diameter
- 1.628 mm
- Area
- 2.08 mm²
- Cu @ 20°C
- 2.525 Ω/kft
- Diameter
- 1.291 mm
- Area
- 1.31 mm²
- Cu @ 20°C
- 4.015 Ω/kft
Interactive comparison
Compare selected AWG sizes
See how diameter or cross-sectional area changes across selected gauges.
Select two or more gauges in the table to compare them.
How to read the scale
A larger AWG number means a smaller wire
- Gauge direction: 4/0 is the largest size shown; 40 AWG is the smallest.
- Six-gauge shortcut: moving six gauge numbers changes diameter by about a factor of two; area changes by about a factor of four.
- Three-gauge shortcut: moving three sizes changes cross-sectional area by about a factor of two.
- Designation: 1/0, 2/0, 3/0, and 4/0 are also called one-aught through four-aught.
What this chart does—and does not—select
This chart answers a geometry question: the nominal diameter and metallic cross-sectional area associated with an AWG designation. It does not determine whether a conductor is suitable for a circuit.
Design boundary
Do not infer ampacity from diameter alone. Conductor material, insulation temperature rating, number of current-carrying conductors, ambient temperature, installation method, terminal ratings, voltage drop, and governing code all affect a final wire selection.
AWG formula and unit conversions
The AWG progression is geometric. With n = 36 for 36 AWG, n = 0 for 1/0, and negative indices for larger aught sizes, the nominal diameter is:
The endpoints are 0.005 inch at 36 AWG and 0.460 inch at 4/0 AWG.
- Diameter conversion
- dmm = 25.4 × din
- Circular mils
- cmil = (1,000 × din)²
- Metric area
- A = πdmm² / 4
Calculations use unrounded formula values internally; displayed values are rounded only at the end. Circular mil is an area unit, even though its definition uses a diameter measured in mils.
Worked AWG lookup examples
Convert 12 AWG to metric area
The table gives a nominal diameter of 2.053 mm. Applying A = πd²/4 gives about 3.31 mm². This is metallic area, not insulated cable outside diameter.
Find a gauge near 2.5 mm²
A target area of 2.5 mm² falls between 13 AWG at about 2.62 mm² and 14 AWG at about 2.08 mm². The nearest nominal AWG by area is 13 AWG. This is a dimensional comparison only, not a code-compliant conductor selection.
Compare 10 and 16 AWG
10 AWG is about 2.588 mm in diameter and 5.26 mm² in area; 16 AWG is about 1.291 mm and 1.31 mm². Six gauge steps nearly halve diameter and quarter area.
AWG data basis and engineering references
Dataset scope: formula-derived nominal geometry for 44 solid round-wire sizes, 4/0 through 40 AWG.
The page uses the defining AWG geometric progression for nominal solid-wire dimensions. Diameter conversions and areas are calculated from that geometry; copper DC resistance is calculated at 20°C from the International Annealed Copper Standard resistivity basis and nominal circular-mil area. Ampacity is intentionally excluded.
- ASTM B258-18(2026), Standard Specification for Standard Nominal Diameters and Cross-Sectional Areas of AWG Sizes of Solid Round Wires Used as Electrical ConductorsCurrent standard scope and controlling subject. Access to the complete ASTM standard may require purchase.
- NBS Handbook 100, Copper Wire TablesPublic-domain historical reference describing the AWG progression, nominal diameter conventions, units, and conductor-property context.
- NBS Circular 31, Copper Wire TablesHistorical NIST/NBS reference for standard copper conductor resistance relationships and temperature basis.
Dataset and source-check details
- Edition / formulation
- ASTM B258-18(2026) scope; AWG geometric progression from 4/0 to 40
- Source-controlled fields
- ASTM subject scope; NBS Handbook 100 gauge endpoints, progression, and unit conventions
- Calculated fields
- Diameter conversions, circular mils, square-millimeter area, and copper DC resistance at 20°C
- Reference conditions
- Nominal bare solid round-wire geometry; copper resistance reference at 20°C
- Known exclusions
- Ampacity, insulation, cable OD, installation method, terminal limits, and code selection
- Rights / download
- Original calculated dataset; visible-row CSV permitted with source attribution retained on page
- Source check
- Source scope and calculations checked September 27, 2026
- Publisher
- Turn2Engineering
AWG wire size questions
No. AWG numbering runs in the opposite direction: a higher gauge number means a smaller conductor diameter and area.
Yes. The standard designation is commonly written 1/0 AWG and spoken “one aught.” The formula index for 1/0 is zero.
No. AWG describes conductor geometry. Insulation, jackets, shielding, strand lay, and manufacturer construction increase the finished cable outside diameter.
Not by itself. Ampacity requires conductor material, temperature rating, installation conditions, adjustment factors, terminal limitations, and the applicable electrical code.
A circular mil is the area of a circle one mil—0.001 inch—in diameter. For a round wire, circular-mil area equals the diameter in mils squared.
12 AWG has a nominal bare solid-conductor diameter of about 2.053 mm and a cross-sectional area of about 3.31 mm².
10 AWG has a nominal bare solid-conductor diameter of about 2.588 mm and a cross-sectional area of about 5.26 mm².
14 AWG has a nominal bare solid-conductor diameter of about 1.628 mm and a cross-sectional area of about 2.08 mm².
No. AWG is a gauge designation based on a geometric wire-size progression, while mm² is a direct measurement of conductor cross-sectional area. Metric conductor sizes therefore do not map exactly to every AWG designation.
Use geometry first, then verify the electrical design
Use this AWG wire size chart to translate a gauge designation into nominal solid-wire diameter and area or to locate the closest listed geometry. For an actual circuit, continue with ampacity, voltage-drop, terminal, insulation, raceway-fill, and code checks.