AWG To kcmil, kcmil To AWG Calculator (+ MCM AWG Wire Chart)

Both kcmil and AWG denote the cross-section of wires (electrical conductors, to be exact). That means we can easily convert kcmil to AWG and AWG to kcmil. Here is what each of these wire size units means:

  • kcmil (or MCM; it’s the same) stands for thousands of circular mils. These are the big wires that carry more than 200 amps. You have 250 kcmil, 300 kcmil, 350 kcmil, 400 kcmil wires all the way to the biggest 2000 kcmil wire.
  • AWG stands for American Wire Gauge. These are standard wires we use in everyday life for below 200 amp service. You have 44 AWG wires, from the biggest 0000 AWG wire (4/0 wire) to the smallest 40 AWG wire.

What would happen if we were to express kcmil wire size in AWG wire size or AWG in kcmil sizes?

Well, first of all, we have to understand that all kcmil wires are bigger (have a larger diameter) than AWG wires. Here is an example that demonstrates that and the labels we are going to use to convert kcmil to AWG.


  • The smallest kcmil wire is a 250 kcmil wire. It has a 126.7 mm2 cross-section and a median ampacity of 255 amps (copper wire at 75°C, according to NEC ampacity charts). 250 kcmil wire converts to -4.72 AWG wire, for example.
  • The biggest AWG wire is a 0000 (4/0) AWG wire. It has a 107 mm2 cross-section and a median ampacity of 230amps (copper wire at 75°C, according to the AWG ampacity chart here). 0000 AWG wire converts to 211.60 kcmil, for example.

As you can see, the biggest AWG wire is already denoted as 0000 AWG or 4/0 AWG. If you want to convert larger kcmil wires to AWG, we will have let’s say 00000 AWG or 5/0 AWG wires. Let’s denote these wires with a negative sign like this: 0000 AWG wire is -4 AWG, 000 AWG wire is -3 AWG, and so on.

The conversion formulas for kcmil to AWG and AWG to kcmil are quite complex:

awg to kcmil formula and kcmil to awg formula

To help everybody out, we have created simple kcmil to AWG calculator (1st calculator) that converts automatically and AWG to kcmil calculator (2nd calculator) that does the reverse. On top of that, you can also consult kcmil to AWG chart where you have 250 kcmil to 2000 kcmil wires converted to theoretical AWG gauge size (1st chart) and the AWG to kcmil chart (2nd chart). Let’s first look at the MCM to AWG calculator:

kcmil To AWG Calculator (1st MCM To AWG Calculator)

This is the 1st calculator. Just insert the kcmil wire size and the calculator will automatically determine what AWG number would such an MCM wire has:


Here is how this calculator works: As an example, slide the slider to 500 kcmil. How many AWG would that be? That will be -7.71 AWG. In a normal way, we would denote this as (7.71/0) AWG or something like 000000 AWG (there should be 7.71 zeros there, hope you get the gist).

Let’s use the reverse calculator to convert AWG to kcmil:

AWG To kcmil Calculator (2nd AWG To MCM Calculator)

This is the 2nd calculator. Just insert the AWG wire size and the calculator will automatically determine what kcmil number (or MCM number) would such an AWG wire has:


For an even easier way to find kcmil and AWG wire numbers, you can use these two charts:

kcmil To AWG Chart (1st MCM To AWG Chart)

kcmil Wire (Or MCM Wire): AWG Wire:
250 kcmil (250 MCM) -4.72 AWG
300 kcmil (300 MCM) -5.51 AWG
350 kcmil (350 MCM) -6.17 AWG
400 kcmil (400 MCM) -6.75 AWG
500 kcmil (500 MCM) -7.71 AWG
600 kcmil (600 MCM) -8.49 AWG
700 kcmil (700 MCM) -9.16 AWG
750 kcmil (750 MCM) -9.46 AWG
800 kcmil (800 MCM) -9.74 AWG
900 kcmil (900 MCM) -10.24 AWG
1000 kcmil (1000 MCM) -10.70 AWG
1250 kcmil (1250 MCM) -11.66 AWG
1500 kcmil (1500 MCM) -12.45 AWG
1750 kcmil (1750 MCM) -13.11 AWG
2000 kcmil (2000 MCM) -13.69 AWG

This kcmil or MCM to AWG chart is quite easy to use. Let’s say you want to know how many AWG is a 100o kcmil wire. As you can see, the 1000 kcmil wire would be -10.70 AWG. Standardly, we would denote this as (10.70/0) AWG or 0000000000 AWG (there should be 10.70 zeros there).

Here is a similar chart for AWG to MCM (or kcmil, it’s the same):

AWG To kcmil Chart (2nd AWG To MCM Chart)

AWG Wire: kcmil Wire (Or MCM Wire):
0000 (4/0) AWG 211.60 kcmil
000 (3/0) AWG 167.81 kcmil
00 (2/0) AWG 133.08 kcmil
0 (1/0) AWG 83.69 kcmil
1 AWG 66.37 kcmil
2 AWG 52.63 kcmil
3 AWG 41.74 kcmil
4 AWG 33.10 kcmil
5 AWG 26.25 kcmil
6 AWG 20.82 kcmil
7 AWG 16.51 kcmil
8 AWG 13.09 kcmil
9 AWG 10.38 kcmil
10 AWG 8.23 kcmil
11 AWG 6.53 kcmil
12 AWG 5.18 kcmil
13 AWG 4.11 kcmil
14 AWG 3.26 kcmil
15 AWG 2.58 kcmil
16 AWG 2.05 kcmil
17 AWG 1.62 kcmil
18 AWG 1.29 kcmil
19 AWG 1.02 kcmil
20 AWG 0.81 kcmil
21 AWG 0.64 kcmil
22 AWG 0.51 kcmil
23 AWG 0.40 kcmil
24 AWG 0.32 kcmil
25 AWG 0.25 kcmil
26 AWG 0.20 kcmil
27 AWG 0.16 kcmil
28 AWG 0.13 kcmil
29 AWG 0.10 kcmil
30 AWG 0.08 kcmil
31 AWG 0.06 kcmil
32 AWG 0.05 kcmil
33 AWG 0.04 kcmil
34 AWG 0.03 kcmil
35 AWG 0.03 kcmil
36 AWG 0.02 kcmil
37 AWG 0.02 kcmil
38 AWG 0.01 kcmil
39 AWG 0.01 kcmil
40 AWG 0.01 kcmil

Hopefully, you can use these two charts to help with MCM to AWG and AWG to MCM conversions. If you have any questions, you can use the comments below and we’ll try to help you out.

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