Conductor area
A = factor x rho x I x L / Vdrop
Electrical calculator
Wire Size Calculator
Size conductors from voltage-drop limits using copper resistivity.
Calculator
Enter values
Results update automatically as you type.
Result
About this calculator
How it works
This calculator estimates minimum copper conductor area from voltage drop. Always check ampacity, installation conditions, and local electrical codes.
Formulas
Formulas used
Allowed voltage drop
Vdrop = Vsupply x allowed percent / 100
Guide
How to use this calculator
- Choose the mode or component type if the calculator provides one.
- Enter known values and select the units beside each input.
- Read the highlighted result first, then use the table for supporting calculated values.
Reference
What the results mean
Minimum copper area
Estimated conductor cross-section required by the voltage-drop limit.
Allowed voltage drop
Maximum voltage loss allowed by the entered percentage.
FAQ
Wire Size Calculator questions
Can I use different units?
Yes. Select the unit beside each input. The calculator converts values internally before solving.
Are the results suitable for final design?
Use results for education, screening, and early design checks. Verify final work against standards, datasheets, and project requirements.
Why does the result update automatically?
The calculator listens for input changes and recalculates as soon as enough valid values are available.
Related
Electrical calculators
AC Power Calculator
Compute real, reactive, and apparent power in single-phase or three-phase AC circuits.
Cutoff Frequency Calculator
Calculate cutoff frequencies for RC and RL filter circuits.
Inductor Calculator
Calculate inductance for air-core or magnetic-core coils.
Ohm's Law Calculator
Find voltage, current, resistance, or power using Ohm's law.
Power Factor Calculator
Estimate power factor and AC circuit efficiency.