Wire, Cable and Voltage Drop

These calculators size conductors from current, voltage and run length. Find the smallest wire or cable, size DC wiring, convert AWG to mm², and check the resistance of a wire and the voltage drop over its length.

Tools in this group

• AWG to mm2 Calculator (AWG to mm² and mm² to AWG) — Pick an AWG or kcmil size to get its area in mm², or enter mm² to find the nearest AWG.
• Cable Size Calculator (mm²) — Enter the load, voltage and cable length to get the minimum cable size in mm² by voltage drop, with mV/A/m.
• DC Wire Size Calculator (12V, 24V, 48V) — Enter the system voltage, current and one-way length to get the wire gauge for your allowed voltage drop.
• Wire Resistance Calculator (Resistance of a Wire) — Pick the wire size, material and length to get its resistance in ohms.
• Voltage Drop Calculator — Enter the circuit, the wire size and the one-way length to get the voltage drop in volts and percent, with every step.
• Wire Bundle Diameter Calculator — Enter how many wires you have and their outside diameter to get the bundle diameter.
• Wire Size Calculator (Wire Gauge) — Enter the circuit, current and length to get the smallest wire size that meets your voltage-drop limit.