Created By : awnish

Reviewed By : Phani Ponnapalli

Last Updated : Apr 10, 2023


Wire Gauge Calculator is a handy tool that determines the resistance per unit length, diameter and cross-section area for the given wire material. Enter gauge type, and wire material details in the input sections and click on the calculate button to check the output within no time.

Steps to Find Wire Resistance per Unit Length

The following is the step by step process of calculating the wire diameter, resistance and cross-sectional area easily.

  • Obtain the diameter of the wire.
  • Square the diameter and multiply it by π/4 to get the area.
  • Divide the resistivity of the wire by the area to check the electrical resistance per unit length.

The American Wire Gauge (AWG) standard | The Standard Wire Gauge (SWG)

The American wire gauge is a logarithmic wire gauge system and it is used to specify the jewelry size. The AWG numbers are inversely proportional to the diameter and cross-sectional area of the wire. The AWG wire gauge system scale is defined in terms of diameter.

The difference in the diameter of each successive gauge is a constant ratio of 931/39. The formulas for wire diameter and cross-sectional area are along the lines.

Diameter = 0.005 inch x 92(36-n)/39

diameter = 0.127 mm x 92(36-n)/39

Area = (π/4) x diameter²

Area = 0.000019635 inch2 x 92(36-n)/19.5

area = 0.012668 mm2 x 92(36-n)/19.5

Standard Wire Gauge (SWG):

This SWG is used to define the thickness of guitar strings and some types of electrical wiring.

The SWG wire gauge chart is as follows:

SWG Gauge Diameter (in) Diameter (mm) Step (in)
7/0 0.5 12.7 0.036
6/0 0.464 11.786 0.032
5/0 0.432 10.973 0.032
4/0 0.4 10.16 0.028
3/0 0.372 9.449 0.024
2/0 0.348 8.839 0.024
0 0.324 8.23 0.024
1 0.3 7.62 0.024
2 0.276 7.01 0.024
3 0.252 6.401 0.02
4 0.232 5.893 0.02
5 0.212 5.385 0.02
6 0.192 4.877 0.016
7 0.176 4.47 0.016
8 0.16 4.064 0.016
9 0.144 3.658 0.016
10 0.128 3.251 0.012
11 0.116 2.946 0.012
12 0.104 2.642 0.012
13 0.092 2.337 0.012
14 0.08 2.032 0.008
15 0.072 1.829 0.008
16 0.064 1.626 0.008
17 0.056 1.422 0.008
18 0.048 1.219 0.008
19 0.04 1.016 0.004
20 0.036 0.914 0.004
21 0.032 0.813 0.004
22 0.0028 0.711 0.004
23 0.0024 0.61 0.002
24 0.022 0.559 0.002
25 0.02 0.508 0.002
26 0.018 0.4572 0.016
27 0.0164 0.4166 0.016
28 0.0148 0.3759 0.0012
29 0.0136 0.3454 0.0012
30 0.0124 0.315 0.0008
31 0.0116 0.2946 0.0008
32 0.0108 0.2743 0.0008
33 0.01 0.254 0.0008
34 0.0092 0.2337 0.0008
35 0.0084 0.2134 0.0008
36 0.0076 0.193 0.0008
37 0.0068 0.1727 0.0008
38 0.006 0.1524 0.0008
39 0.0052 0.1321 0.0004
40 0.0048 0.1219 0.0004
41 0.0044 0.1118 0.0004
42 0.004 0.1016 0.0004
43 0.0036 0.0914 0.0004
44 0.0032 0.0813 0.0004
45 0.0028 0.0711 0.0004
46 0.0024 0.061 0.0004
47 0.002 0.508 0.0004
48 0.0016 0.0406 0.0002
49 0.0012 0.0305 0.0002
50 0.001 0.0254 0.0002

Electrical Resistance per Unit Length

The electrical resistance per unit length is nothing but the wire resistance in one unit length of the wire. Get the fundamental property of the electrical conductor material that forms the wire resistivity. The equation to find the wire resistivity is

ρ = R x (A/l)

The resistance per unit length of the wire is

R/l = ρ/A

Where,

R is the electrical resistance

A is the cross-sectional area of the wire

l is the wire length

Physicscalc.Com has got concepts like friction, acceleration due to gravity, water pressure, gravity, and many more along with their relevant calculators all one under one roof.

FAQ's on Wire Gauge Calculator

1. What are the types of wire gauges?

The two different types of the gauge are American Wire Gauge (AWG) and Standard Wire Gauge (SWG).


2. What is the formula to calculate the electrical resistance per unit length?

Divide the resistivity of the wire by the cross-sectional area to check the resistance per unit length. The formula is R/l = ρ/A.


3. How to use a wire gauge size calculator?

Choose either AWG or SWG as the wire gauge type and wire material type. And hit on the calculate button to get the result. The result has the diameter, cross-sectional area and electrical resistance per length of the wire.


4. How to gauge a wire?

 

The three simple methods to gauge a wire is stripping insulation, gauging round solid wire and gauging standard wire.