Wire Gauge Calculator

Wire AWG from current capacity and voltage drop.

Current (A)

System Voltage (V)

Wire Length (m, one way)

Max Voltage Drop (%)

Tab to move between fields

Recommended AWG

Voltage Drop (V)

0.25

Wire Diameter (mm)1.63

Voltage Drop (%)2.07

Voltage at Load (V)11.75

Total Wire Resistance (Ω)0.05

Power Loss (W)1.24

Wire Max Current (A)32

Required Area Mm21.44

How to Use This Calculator

How the result changes with Current (A)

Current (A): Maximum current the wire must carry in amps.
System Voltage (V): Supply voltage of your circuit (e.g. 5V, 12V, 24V).
Wire Length (m, one way): One-way wire length in meters. Total run (supply + return) is 2x this.
Max Voltage Drop (%): Maximum acceptable voltage drop as a percentage (3% is standard, 5% for non-critical).

Recommended AWG: Smallest wire gauge (largest number) meeting both current and voltage drop requirements.
Wire Diameter (mm): Conductor diameter of recommended gauge.
Voltage Drop (V): Actual voltage drop across the full wire run (both directions).
Voltage Drop (%): Voltage drop as percentage of supply voltage.
Voltage at Load (V): Actual voltage delivered to the load after wire losses.
Total Wire Resistance (Ω): Round-trip wire resistance (both conductors).
Power Loss (W): Power dissipated as heat in the wire (I²R).
Wire Max Current (A): Maximum safe current for the recommended gauge (chassis wiring).

Identify Input Parameters
4 parameters
Current (A) = 5, System Voltage (V) = 12, Wire Length (m, one way) = 3, Max Voltage Drop (%) = 3 = 4 input(s) provided
Calculate Recommended AWG
Recommended AWG = 2
14 = 14
Calculate Voltage Drop
Voltage Drop = recTotalRes * currentAmps
0.2485 = 0.2485
Calculate Wire Diameter
Wire Diameter = awgTable[awgTable.length - 1].diamMm
1.628 = 1.628
Calculate Voltage Drop
Voltage Drop = (actualVoltageDrop / voltage) * 100
2.07 = 2.07