Wire gauge charts printed in electrical handbooks only list the common sizes — 14, 12, 10, 8 AWG and so on — because circular mil area doesn't come from a simple lookup, it comes from a geometric formula. This calculator computes it directly, so any AWG from 14 down to 4/0 works exactly, not just the ones that made it onto someone's chart.
Voltage drop calculator, single-phase or three-phase
Pick single-phase/DC or three-phase, copper or aluminum, then enter the wire gauge, one-way run length, load current, and supply voltage — the calculator applies the correct multiplier (2× for single-phase, √3 for three-phase) automatically.
Wire size voltage drop chart, without the gaps
Circular mils are derived from the standard AWG geometric formula rather than copied from a table, so every gauge from 14 AWG to 4/0 (and everything between) comes out matching published reference values exactly.
What wire size do I need — the 5% rule
5% is the commonly cited maximum acceptable voltage drop under full load for a branch circuit. This calculator flags any result over that threshold with a warning, so you know at a glance whether to size up.
