Purpose-set for 24-volt systems — trucks, larger solar arrays, landscape lighting and industrial control — with the same three solvers: drop, minimum wire size, and maximum cable length.
At 24 V, a 3% budget is just 0.72 volts — the entire allowance for the round trip through both conductors. The shortcut for any 24 V run: maximum one-way feet ≈ (0.72 × 1000) ÷ (2 × amps × Ω/kft of the wire). The calculator's Max Length tab does exactly this for every size at once.
Aim for 3% (0.72 V) for electronics, lighting and charging circuits; up to 10% is sometimes tolerated for non-critical resistive loads. Battery-to-inverter cabling should stay under 2%.