Empowering a brighter world through superior education is our commitment.

Online Calculators & Tools

Wire Gauge Size Chart

American wire gauge (AWG) size calculator and chart.

Wire gauge calculator

Select gauge #: 
Or enter gauge #:AWG
Select wire type: 
Resistivity:Ω·m
 
Diameter in inches:in
Diameter in millimeters:mm
Cross sectional area in kilo circular mils:kcmil
Cross sectional area in square inches:in2
Cross sectional area in square millimeters:mm2
Resistance per 1000 feet*:Ω/kft
Resistance per 1000 meters*:Ω/km

* @ 68°F or 20°C

** Diameter and cross sectional area do not include the insulation.

*** Results may change with real wires: different resistivity of material and number of strands in wire

Voltage drop calculator

AWG chart

AWG #Diameter
(inch)
Diameter
(mm)
Area
(kcmil)
Area
(mm2)
0000 (4/0)0.460011.6840211.6000107.2193
000 (3/0)0.409610.4049167.806485.0288
00 (2/0)0.36489.2658133.076567.4309
0 (1/0)0.32498.2515105.534553.4751
10.28937.348183.692742.4077
20.25766.543766.371333.6308
30.22945.827352.634826.6705
40.20435.189441.741321.1506
50.18194.621333.102416.7732
60.16204.115426.251413.3018
70.14433.664920.818310.5488
80.12853.263616.50978.3656
90.11442.906413.09276.6342
100.10192.588210.38305.2612
110.09072.30488.23414.1723
120.08082.05256.52993.3088
130.07201.82785.17852.6240
140.06411.62774.10672.0809
150.05711.44953.25681.6502
160.05081.29082.58271.3087
170.04531.14952.04821.0378
180.04031.02371.62430.8230
190.03590.91161.28810.6527
200.03200.81181.02150.5176
210.02850.72290.81010.4105
220.02530.64380.64240.3255
230.02260.57330.50950.2582
240.02010.51060.40400.2047
250.01790.45470.32040.1624
260.01590.40490.25410.1288
270.01420.36060.20150.1021
280.01260.32110.15980.0810
290.01130.28590.12670.0642
300.01000.25460.10050.0509
310.00890.22680.07970.0404
320.00800.20190.06320.0320
330.00710.17980.05010.0254
340.00630.16010.03980.0201
350.00560.14260.03150.0160
360.00500.12700.02500.0127
370.00450.11310.01980.0100
380.00400.10070.01570.0080
390.00350.08970.01250.0063
400.00310.07990.00990.0050

Wire gauge calculations

Wire diameter calculations

The n gauge wire diameter dn in inches (in) is equal to 0.005in times 92 raised to the power of 36 minus gauge number n, divided by 39:

dn (in) = 0.005 in × 92(36-n)/39

The n gauge wire diameter dn in millimeters (mm) is equal to 0.127mm times 92 raised to the power of 36 minus gauge number n, divided by 39:

dn (mm) = 0.127 mm × 92(36-n)/39

Wire cross sectional area calculations

The n gauge wire's cross sercional area An in kilo-circular mils (kcmil) is equal to 1000 times the square wire diameter d in inches (in):

An (kcmil) = 1000×dn2= 0.025 in2 × 92(36-n)/19.5

The n gauge wire's cross sercional area An in square inches (in2) is equal to pi divided by 4 times the square wire diameter d in inches (in):

An (in2) = (π/4)×dn2= 0.000019635 in2 × 92(36-n)/19.5

The n gauge wire's cross sercional area Anin square millimeters (mm2) is equal to pi divided by 4 times the square wire diameter d in millimeters (mm):

An (mm2) = (π/4)×dn2= 0.012668 mm2 × 92(36-n)/19.5

Wire resistance calculations

The n gauge wire resistance R in ohms per kilofeet (Ω/kft) is equal to 0.3048×1000000000 times the wire's resistivity ρ in ohm-meters (Ω·m) divided by 25.42 times the cross sectional area An in square inches (in2):

Rn (Ω/kft) = 0.3048 × 109 ×ρ(Ω·m) / (25.42× An (in2))

The n gauge wire resistance R in ohms per kilometer (Ω/km) is equal to 1000000000 times the wire's resistivity ρ in ohm-meters (Ω·m) divided by the cross sectional areaAn in square millimeters (mm2):

Rn (Ω/km) = 109× ρ(Ω·m) / An(mm2)