Voltage Drop Calculator — NEC, BS7671, AS/NZS 3000, CEC, IEC | VoltageLab
Electrical Calculator

Voltage Drop Calculator

NEC · BS7671 · AS/NZS 3000 · CEC · IEC 60364 — with code references

⚙️ Select Standard & System Type
🇺🇸 NEC (USA)
🇬🇧 BS7671 (UK)
🇦🇺 AS/NZS 3000
🇨🇦 CEC (Canada)
🌐 IEC 60364
📐 Circuit Parameters
Please fill in all required fields (Voltage, Current or Load, and Length).
PASS
Voltage Drop (V)
Drop (%)
End Voltage (V)
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Formulas: Single-phase & DC: VD = (2 × K × I × L) / A  |  Three-phase: VD = (√3 × K × I × L) / A
K = resistivity (copper: 12.9 for AWG/ft, 0.0172 for mm²/m | aluminium: 21.2, 0.0282)
Results are indicative. Always verify with a licensed electrical engineer before installation.