AWG to mm² Wire Size Converter

How it is calculated

Choose a direction, then enter one number. From AWG to area the tool uses A = 0.012668 × 92(36 − AWG) / 19.5, where A is the conductor cross-section in mm². From area to AWG it inverts this: AWG = 36 − 19.5 × ln(A / 0.012668) / ln(92). The conductor diameter is then d = √(4A / π) in mm, which treats the wire as a solid round conductor. The AWG figure is shown with one decimal and areas and diameters with four. The area given in mm² must be greater than zero. An AWG entry is not limited, so values of 0 or below also compute. The result is the geometric size only, not a current rating.

Common mistakes

• Leaving the direction on AWG to mm² when typing an area. 2.5 would be read as gauge 2.5 and give about 29.95 mm².
• Assuming a bigger AWG number is a bigger wire. It is the opposite: 12 AWG is thicker than 20 AWG.
• Using the result as the wire's current rating. The tool gives only geometry; ampacity depends on insulation, temperature and installation.
• Treating the AWG result in the mm² to AWG direction (for example 13.2) as an orderable size. Real gauges are whole numbers, so round to a standard neighbour and check which side is safer.
• Applying the result to stranded wire. The diameter assumes one solid round conductor, so a stranded cable of the same copper area is somewhat thicker overall.