ELECTRICAL TOOL · NO ACCOUNT REQUIRED

12/24 V wire voltage-drop explorer.

Explore how current, copper wire length and gauge affect calculated DC voltage drop—without pretending this sizes a safe circuit.

**Count both conductors**A 20 ft one-way circuit has 40 ft of conductor. At 10 A and 1.588 ohms per 1,000 ft, calculated drop is 0.6352 V. Fuse is shown conceptually; protection ratings, routing and installation requirements are not specified.Reference: Blue Sea Systems — choosing wire size

INTERACTIVE CALCULATOR

Adjust the inputs. Estimates update instantly; nothing is uploaded.

System voltageVCurrentAONE-WAY cable lengthftCopper wire gauge

YOUR ESTIMATE

Enter measurements to see the calculation.

How it works

Voltage drop = current × (round-trip copper conductor length ÷ 1,000) × conductor resistance (ohms/1,000 feet). Reference resistances are around 20°C.

Important limitation

This is NOT a safe wire-sizing or fuse-sizing tool. Ampacity, bundling, insulation temperature, marine environment, terminals, voltage source and ABYC requirements still govern.

IF YOU WANT THE WHOLE STORY

The math is the beginning.

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PUT THE RESULT TO WORK

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