Wire Size Calculator: AWG for Amps, Length, Voltage (NEC-Based)

Wire Size Calculator: AWG for Amps, Length, Voltage

NEC-based wire sizing — enter amps, distance, voltage; get AWG plus voltage-drop math.

NEC Table 310.16 wire ampacity by AWG size — PES Supply chart

By Jennifer Kirstens · August 30, 2026 · 7 min read

Wire Size Calculator (Amps, Distance, Voltage)

NEC-based AWG sizing for THHN copper or aluminum with voltage-drop and Table 310.16 (75°C) ampacity check.
Reference: NEC Wire Ampacity Chart. Confirm with the AHJ and NEC 210.19, 215.2, 310.16.
Related PES calculators: Duct Sizing · Wire Size · Breaker Sizing

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