Wire Size Calculator
Estimate the minimum cable size for a circuit. A correct size must satisfy two things at once — carry the current without overheating, and keep the voltage drop over the run within limits. This tool checks both and shows which one governs. It is an indicative planning aid; the final size must be set by a licensed electrician to the current code (IS 732) for your actual installation.
Codes commonly limit total voltage drop to about 3–5% from the supply to the point of use.
Copper, 1-phase — drawing 10.9 A over 20 m, at ~2.2% drop.
Indicative only. This uses conservative planning values for current capacity and a simple resistance model for voltage drop. Real cable sizing depends on the installation method, grouping, ambient temperature, the protective device, and derating factors this tool does not model. Use it to sanity-check, never to finalise. The cable size, protection and earthing for your circuit must be set by a licensed electrician to IS 732 and the National Electrical Code.
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