Voltage Drop Calculator — Wire Gauge, Length, and Amps to Voltage Drop %
Enter wire gauge, run length, and current (amps) to calculate voltage drop percentage and acceptability.
Wire Parameters
How to Use the Voltage Drop Calculator
Enter wire gauge, run length, and current (amps) to calculate voltage drop percentage and acceptability.
This free online voltage drop calculator is designed for electricians and field technicians who need fast, accurate results on the job or during the estimating process. No account required — enter your values and get results instantly.
When to Use This Tool
- 1.During new construction estimates and material takeoffs
- 2.When verifying calculations in the field before ordering materials
- 3.For proposal and quote preparation — give clients accurate numbers
- 4.As a cross-check against manual calculations or software output
- 5.For training new technicians on correct sizing procedures
Important Notes
Results from this voltage drop calculator are estimates based on standard industry formulas and typical conditions. Always verify critical calculations with manufacturer specifications, local codes, and a licensed electrician before proceeding with installation or ordering materials. Actual requirements may vary based on local building codes, site conditions, and project-specific factors.
Also from ProvenQuote
Own Your Electrical Market
Exclusive electrical leads in your city. One electrician. Every inquiry. $2,400–$7,200/mo/mo.
More Free Electrical Tools
Wire Size Calculator
Enter amperage, voltage, and wire run distance to calculate minimum AWG wire gau...
Electrical Load Calculator
Enter appliances and circuits to calculate total electrical load in amps and req...
Conduit Fill Calculator
Enter wire count and gauge to calculate minimum conduit size per NEC 40% fill ru...
Circuit Breaker Size Calculator
Enter load in watts and voltage to calculate required circuit breaker size and w...