Wire Size Calculator

Calculate the correct wire gauge (AWG) for electrical installations based on current, distance, and voltage drop requirements.

Wire Sizing Parameters

NEC recommends 3% for branch circuits, 5% total

Recommended Wire Size

12 AWG
CopperSingle Phase

Voltage Drop Analysis

Actual Voltage Drop3.18 V (2.65%)
Wire Resistance0.1588 ohms
Power Loss in Wire63.52 W (2.65%)

Ampacity Check

Wire Ampacity20 A
Load Current20 A
Safety Margin0.0%

Wire Details

Required Circular Mils5761
Selected Wire Circular Mils6530
Total Wire Length100 ft
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Editorial Note

MyCalcBuddy Editorial Team

This page is maintained as an educational calculator reference.

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Formula Source: Standard Mathematical References

by Various

🔄Last reviewed: May 2026
✓Formula checks are based on standard references and internal QA review.