About
About WattWise
Practical electrical calculators, reference charts, and guides for electricians, contractors, and anyone who works with real circuits and real bills.
Who this site is for
WattWise is built for working electricians and the people around them: apprentices learning the math, journeymen checking numbers in the field, contractors pricing jobs, facility managers running small commercial sites, and advanced homeowners who want to understand what their electrician is telling them.
Why it exists
Electrical work runs on numbers that are easy to get slightly wrong: load current on a circuit, demand on a service, payback on a solar quote, the blended cost of charging an EV, or which half of a commercial bill is actually the demand charge. Small errors compound into tripped breakers, failed inspections, oversized quotes, or lost savings. This site exists to make those numbers checkable in minutes, with every assumption visible on the page.
What you will find here
- Calculators with visible math: every input, formula, and output is shown, so a result can be verified by hand or against code tables.
- Reference charts and rate baselines: national averages and typical values, always dated, always labeled as starting points rather than local facts.
- Practical guides: worked examples that pair a parameter table with a hand calculation you can reproduce, written so an apprentice can follow and a journeyman can skim.
- A private Workspace: save assumptions and reports for jobs, quotes, and comparisons without exposing client data.
How content is produced and reviewed
Each calculator ships with machine-checked test cases: fixed inputs must reproduce fixed outputs before the tool is published. Rate baselines carry a data year and are reviewed annually against U.S. Energy Information Administration figures. Guides cite their sources and show the full arithmetic of every worked example. When a reader reports an error through Contact, the page is corrected and the correction is noted.
What this site is not
WattWise is a planning and reference tool. It is not a substitute for the National Electrical Code, the authority having jurisdiction, manufacturer instructions, or the judgment of a licensed electrician on site. A calculator output is not an approval, a permit, a quote, or a guarantee of performance. Read the Disclosure before relying on any result.
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