Common US Wire Gauges – AWG Gauges Vs Current Ratings - Resources For Electrical & Electronic Engineers (2024)

The AWG – American Wire Gauge – is used as a standard method denoting wire diameter, measuring the diameter of the conductor (the bare wire) with the insulation removed. AWG is sometimes also known as Brown and Sharpe (B&S) Wire Gauge.

The AWG table below is for a single, solid, round conductor. Because of the small gaps between the strands in a stranded wire, a stranded wire with the same current-carrying capacity and electrical resistance as a solid wire, always have a slightly larger overall diameter.

The higher the number – the thinner the wire. Typical household wiring is AWG number 12 or 14. Telephone wire is typical AWG 22, 24, or 26.

The table below indicates the current ratings of PVC-insulated single and multicore wiring cables. Be aware that the current load depends on installation method – the enclosure – and how well the resistance heat is removed from the cable.

Operating temperature of the conductor, ambient temperature and type of conductor insulation is important. Always check the manufactures data before detailed engineering.

AWGDiameter
(mm)
Diameter
(in)
Square
(mm2)
Resistance
Copper
(ohms/1000m)
(Ohms/1000 ft)
Typical Max. Current Load Ratings – Copper (amps)1)
Single CoreMulticore
up to 3 cores4 – 6 cores7 – 24 cores25 – 42 cores43 and above
400.08.0.00503420
390.09.0.00642700
380.100.00400.00782190
370.110.00450.00951810
360.130.00500.0131300
350.140.00560.0151120
340.160.00630.020844
330.180.00710.026676
320.200.00800.031547
300.250.0100.049351
280.330.0130.080232
270.360.0140.096178
260.410.0160.13137
250.450.0180.16108
240.510.0200.20883.521.61.41.21.0
220.640.0250.33525.032.42.11.81.5
200.810.0320.50346.054.03.53.02.5
181.00.0400.82229.575.64.94.23.5
161.30.0511.31320108.07.06.05.0
141.60.0642.18.5241512109.07.5
131.80.0722.66.8
122.10.0813.35.4342016141210
102.60.105.33.4523024211815
83.30.138.32.2754032282420
64.10.1713.31.5955544383327
45.20.2021.20.801207056494235
326.71548064564840
26.50.2633.60.501709576665757
17.40.2942.40.4018011088776655
0 (1/0)8.30.3353.50.31200
00 (2/0)9.30.3767.40.25225
000 (3/0)10.40.4185.00.20275
0000 (4/0)11.70.461070.16325
250127345
300152390
400178415

1) Current ratings for up to 1000 V, PVC-insulated single and multicore wiring cables, ambient temperature up to 30oC

The higher the gauge number, the smaller the diameter, and the thinner the wire.

Because of less electrical resistance a thicker wire carries more current with less voltage drop than a thinner wire. For longer distances it may be necessary to increase wire diameter – reducing the gauge – to limit voltage drop.

Correction-factors at ambient temperature above 30oC

  • ambient temperature 31 – 40 oC: correction factor = 0.82
  • ambient temperature 41 – 45 oC: correction factor = 0.71
  • ambient temperature 45 – 50 oC: correction factor = 0.58

American Wire Gauge Conductor Size Table

American wire gauge (AWG) is a standardized wire gauge system for the diameters of round, solid, nonferrous, electrically conducting wire. The larger the AWG number or wire guage, the smaller the physical size of the wire. The smallest AWG size is 40 and the largest is 0000 (4/0). AWG general rules of thumb – for every 6 gauge decrease, the wire diameter doubles and for every 3 gauge decrease, the cross sectional area doubles. Note – W&M Wire Gauge, US Steel Wire Gauge and Music Wire Gauge are different systems.

American Wire Gauge (AWG) Sizes and Properties Chart / Table

Table 1 lists the AWG sizes for electrical cables / conductors. In addition to wire size, the table provides values load (current) carrying capacity, resistance and skin effects. The resistances and skin depth noted are for copper conductors. A detailed description of each conductor property is described below Table 1.

Table 1: American Wire Gauge (AWG) Cable / Conductor Sizes and Properties

AWGDiameter
[inches]
Diameter
[mm]
Area
[mm2]
Resistance
[Ohms / 1000 ft]
Resistance
[Ohms / km]
Max Current
[Amperes]
Max Frequency
for 100% skin depth
0000 (4/0)0.4611.6841070.0490.16072302125 Hz
000 (3/0)0.409610.40384850.06180.202704239160 Hz
00 (2/0)0.36489.2659267.40.07790.255512190200 Hz
0 (1/0)0.32498.2524653.50.09830.322424150250 Hz
10.28937.3482242.40.12390.406392119325 Hz
20.25766.5430433.60.15630.51266494410 Hz
30.22945.8267626.70.1970.6461675500 Hz
40.20435.1892221.20.24850.8150860650 Hz
50.18194.6202616.80.31331.02762447810 Hz
60.1624.114813.30.39511.295928371100 Hz
70.14433.6652210.50.49821.634096301300 Hz
80.12853.26398.370.62822.060496241650 Hz
90.11442.905766.630.79212.598088192050 Hz
100.10192.588265.260.99893.276392152600 Hz
110.09072.303784.171.264.1328123200 Hz
120.08082.052323.311.5885.208649.34150 Hz
130.0721.82882.622.0036.569847.45300 Hz
140.06411.628142.082.5258.2825.96700 Hz
150.05711.450341.653.18410.443524.78250 Hz
160.05081.290321.314.01613.172483.711 k Hz
170.04531.150621.045.06416.609922.913 k Hz
180.04031.023620.8236.38520.94282.317 kHz
190.03590.911860.6538.05126.407281.821 kHz
200.0320.81280.51810.1533.2921.527 kHz
210.02850.72390.4112.841.9841.233 kHz
220.02540.645160.32616.1452.93920.9242 kHz
230.02260.574040.25820.3666.78080.72953 kHz
240.02010.510540.20525.6784.19760.57768 kHz
250.01790.454660.16232.37106.17360.45785 kHz
260.01590.403860.12940.81133.85680.361107 kHz
270.01420.360680.10251.47168.82160.288130 kHz
280.01260.320040.08164.9212.8720.226170 kHz
290.01130.287020.064281.83268.40240.182210 kHz
300.010.2540.0509103.2338.4960.142270 kHz
310.00890.226060.0404130.1426.7280.113340 kHz
320.0080.20320.032164.1538.2480.091430 kHz
330.00710.180340.0254206.9678.6320.072540 kHz
340.00630.160020.0201260.9855.7520.056690 kHz
350.00560.142240.0163291079.120.044870 kHz
360.0050.1270.0127414.813600.0351100 kHz
370.00450.11430.01523.117150.02891350 kHz
380.0040.10160.00797659.621630.02281750 kHz
390.00350.08890.00632831.827280.01752250 kHz
400.00310.078740.00501104934400.01372900 kHz

AWG Notes: American Wire Gauge (AWG) is a standardized wire gauge system used predominantly in the United States to note the diameter of electrically conducting wire. The general rule of thumb is for every 6 gauge decrease the wire diameter doubles and every 3 gauge decrease doubles the cross sectional area.

Diameter Notes: A mil is a unit of length equal to 0.001 inch (a “milli-inch” or a “thousandth of one inch”) ie. 1 mil = 0.001″.

Resistance Notes: The resistance noted in the table above is for copper wire conductor. For a given current, you can use the noted resistance and apply Ohms Law to calculate the voltage drop across the conductor.

Current (ampacity) Notes: The current ratings shown in the table are for power transmission and have been determined using the rule of 1 amp per 700 circular mils, which is a very conservative rating. For reference, the National Electrical Code (NEC) notes the following ampacity for copper wire at 30 Celsius:
14 AWG – maximum of 20 Amps in free air, maximum of 15 Amps as part of a 3 conductor cable;
12 AWG – maximum of 25 Amps in free air, maximum of 20 Amps as part of a 3 conductor cable;
10 AWG – maximum of 40 Amps in free air, maximum of 30 Amps as part of a 3 conductor cable.

Check your local electrical code for the correct current capacity (ampacity) for mains and in wall wiring.

Skin Effect and Skin Depth Notes: Skin effect is the tendency of an alternating electric current (AC) to distribute itself within a conductor so that the current density near the surface of the conductor is greater than that at its core. That is, the electric current tends to flow at the “skin” of the conductor. The skin effect causes the effective resistance of the conductor to increase with the frequency of the current. The maximum frequency show is for 100% skin depth (ie. no skin effects).

Common US Wire Gauges – AWG Gauges Vs Current Ratings - Resources For Electrical & Electronic Engineers (1)

American Wire Guage (AWG) Wire Sizes

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