About JobsiteWire

JobsiteWire is a free collection of electrical calculators built for one situation: an electrician or apprentice on a jobsite who needs a number now. No signup, no app to install, no waiting for a bloated page — open the tool, punch in the values, get the answer with the reasoning behind it.

Every calculator uses standard formulas and commonly published industry values, computes entirely in your browser, and keeps working offline once the page has loaded. Inputs are sized for gloved hands, results update as you type, and each result can be shared or bookmarked by copying the page URL — the inputs travel with it.

What JobsiteWire is not

JobsiteWire is a reference tool, not a design authority. The results are estimates based on standard formulas and commonly published values; they don't know your local amendments, your ambient temperatures, or your inspector. Electrical installations must comply with your locally adopted electrical code and should be performed or verified by a licensed electrician. This site is not affiliated with NFPA and does not reproduce NEC content.

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