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Wire Size Calculator

Suggest a basic copper wire size from current using a simplified reference ampacity table.

Calculator

Enter your values and select Calculate.

Result Summary

Review the main answer, supporting values, chart breakdown, and calculation details.

Result Breakdown

Calculation Details

MetricValueNote

How it works

Suggest a basic copper wire size from current using a simplified reference ampacity table. Use the units shown in the calculator and review every assumption before using the result.

Formula

The tool chooses the first reference gauge whose simplified ampacity is at least the entered current.

Worked example

This is a planning aid only; installation requirements depend on insulation, temperature, terminals, bundling and code rules.

Important assumptions

This tool is designed for planning and comparison. Real-world prices, manufacturer ratings, building requirements, lender terms, electrical codes, tolerances, and product specifications can vary.

Frequently asked questions

Is this calculator free?

Yes. It runs in your browser and does not require an account.

Are the results exact?

The math is deterministic for the entered values, but the result depends on inputs and assumptions. Verify safety-critical, financial, code-related, towing, fitment, and manufacturer-specific decisions with authoritative information.

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