- 1). Determine the gauge of the wire. This should be displayed on the wire packaging. For higher gauge (smaller diameter) wire, this can also be determined by using wire strippers. Most wire strippers have a series of holes that are identified by wire gauge size. Cut and strip a section of wire and insert the wire in the holes to determine the wire gauge.
- 2). Calculate wire OD based on the wire gauge using the formula D(AWG) = 0.005 x 92^ ((36-AWG)/39)inch. Using a scientific calculator, enter 36 in the calculator and subtract (-) the wire gauge. Divide (/) this number by 39. Record this number. Enter 92 in the calculator, hit the exponential button (the button that is a y with a superscript x), and enter the result that was recorded from the previous step. Multiply this result by 0.005. The result is the diameter (OD) of the wire as measured in inches.
- 3). Check your work using a conversion table (see References).
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