Estimate the Length of a Wire
You can use this calculator to estimate how much wire is left on a spool.
- Start by measuring the resistance of the length of wire. Use an ohmmeter to measure the resistance of the wire. If you use a 2-wire measurement the calculator assumes you have 0.2 ohms of lead resistance. If you make a four-wire measurement the estimate will be more accurate.
- Enter the resistance into the calculator.
- Select the wire gauge on the calculator.
- Click the “Calculate Wire Length” button.