AWG 0 carrying 25 A — 0.16 V over 10 m
53.475 mm² of copper, 0.00032 Ω per metre. Carrying 25 A, a ten-metre run there and back loses 0.16 V.
This gauge handles it · Current it handles 122.2A
- Diameter
- 8.251 mm
- Cross-section
- 53.475 mm²
- Resistance per metre
- 0.00032 Ω
- Current it handles
- 122.2 A
- Drop over 10 m
- 0.16 V
- Heat per metre
- 0.2 W
Length within 3%
Lose the same 0.36 V and it is 3% of a 12 V system but 0.16% of a 230 V one. That is why car wiring looks so thick, and why a long 12 V light run dims at the far end. This page works out the length that stays under 3% for each voltage separately.
- car 12 V22.4 m
- truck 24 V44.8 m
- North America 120 V223.8 m
- Europe 230 V429 m
The match in the other family
The United States names wire by AWG number; most of the world names it by cross-section in mm². The two never line up exactly, so each page shows the nearest match by area. When substituting, err toward the thicker one.
16mm²16mm²Nearby cells
Same gauge, other currents
Same current, other gauges
How to read this
- The length is the distance from source to device. The return trip is already counted.
- Figures are for copper. Aluminium of the same size has about 1.6 times the resistance.
- The "current it handles" is a cautious estimate. Real installations follow the local code table.
- A wire running hot and a lamp dimming at the far end are two different problems. Pick a gauge that answers both.
Frequently asked questions
Q. Can AWG 0 carry 25 A?
Yes. This gauge is comfortable up to 122.2 A.
Q. How far can I run it?
The drop stays under 3% for 429 m at 230 V, 223.8 m at 120 V, or 22.4 m at 12 V.
Q. How many mm² is AWG 0?
53.475 mm², from a diameter of 8.251 mm. The nearest size in the other family is 16mm².
Q. How hot does the wire get?
Every metre turns 0.2 W into heat. Over ten metres that is a 2.0 W heater left running.