Recommended car stereo power and ground and speaker wire sizes

Ground cables must be the same size (or larger) than the power cable. When choosing the cross-section of the power cable, always consider the RMS power of the stereo system in watts. On the Internet, recommended sizes are often given in AWG (American Wire Gauge) units. Below is a table for converting AWG cross-section units to square millimeters (Table 2)
Although wire sizes smaller than 10AWG may be acceptable for current, we recommend using the smallest current wire size of 10AWG for a 100 watt RMS or larger stereo/amplifier. The goal is to give the amplifier as much current as it needs for optimal performance.
Table 1. Car radio cable cross-section
Recommended car stereo cable cross-section by RMS current strength and length | |||||
Total RMS Power (watts) RMS power |
Distance | ||||
1,2m | 2,4m | 3,6m | 4,8m | 6m | |
100 | 10 AWG | 10 AWG | 8 AWG | 8 AWG | 4 AWG |
200 | 10 AWG | 8 AWG | 8 AWG | 4 AWG | 4 AWG |
400 | 8 AWG | 8 AWG | 4 AWG | 4 AWG | 4 AWG |
600 | 8 AWG | 4 AWG | 4 AWG | 4 AWG | 4 AWG |
800 | 4 AWG | 4 AWG | 4 AWG | 2 AWG | 2 AWG |
1000 | 4 AWG | 4 AWG | 2 AWG | 2 AWG | 2 AWG |
1400 | 4 AWG | 2 AWG | 2 AWG | 2 AWG | 2 AWG |
Table 2. Corresponding square millimeters of AWG
AWG | mm2 |
30 | 0.05 |
28 | 0.08 |
26 | 0.14 |
24 | 0.25 |
22 | 0.34 |
21 | 0.38 |
20 | 0.50 |
18 | 0.75 |
17 | 1.0 |
16 | 1.5 |
14 | 2.5 |
12 | 4.0 |
10 | 6.0 |
8 | 10 |
6 | 16 |
4 | 25 |
2 | 35 |
1 | 50 |
1/0 | 55 |
2/0 | 70 |
3/0 | 95 |
4/0 | 120 |
300MCM | 150 |
350MCM | 185 |
500MCM | 240 |
600MCM | 300 |
750MCM | 400 |
1000MCM | 500 |