Wire Gauge & Ampacity Calculator
Calculate the minimum wire gauge required for a given current load and distance
About this calculator
The Wire Gauge & Ampacity Calculator helps electricians, engineers, and DIY enthusiasts determine the correct wire size for electrical installations based on current load and wire run distance. This tool ensures electrical safety by preventing voltage drop and overheating, which can cause equipment malfunction, energy waste, or fire hazards. By calculating the minimum required wire gauge (AWG), users can select appropriate conductors that meet electrical codes and maintain system efficiency while avoiding costly oversizing.
How to use
Enter the current load in amperes that will flow through the wire, then input the one-way distance the wire will run in feet. Select your wire type (copper or aluminum) and voltage if applicable. The calculator will display the minimum recommended wire gauge (AWG) needed to safely carry the load over the specified distance while maintaining proper voltage levels.
Frequently asked questions
What happens if I use a wire gauge that's too small?
Using undersized wire causes voltage drop, overheating, reduced equipment performance, and potential fire hazards due to excessive resistance.
Can I use a larger wire gauge than recommended?
Yes, using larger gauge wire is safe and reduces voltage drop further, but increases material costs unnecessarily.
Does wire length affect the required gauge?
Yes, longer wire runs require larger gauge wire to compensate for increased resistance and prevent excessive voltage drop.