About
About GeneratorCalc
Practical generator calculators, load lists, and guides for backup-power planning: sizing, fuel and runtime, installation, running cost, and maintenance.
Who this site is for
GeneratorCalc is built for anyone sizing or running a generator: homeowners planning standby power, contractors pricing installs, facility managers running prime-power sites, and technicians checking fuel, load, and maintenance numbers in the field.
Why it exists
Generator work runs on numbers that are easy to get slightly wrong: running load plus motor starting surge, derated kW at altitude and heat, fuel burn at the real load factor, runtime on the usable tank, and the maintenance hours that trigger service. Small errors compound into an undersized set, an empty tank, a failed inspection, or lost money. 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 fuel tables and baselines: typical consumption and service intervals, always dated, always labeled as starting points rather than model-specific facts.
- Practical guides: worked examples that pair a parameter table with a hand calculation you can reproduce, written so a homeowner can follow and a contractor 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. Fuel and service baselines carry a data year and are reviewed annually against manufacturer tables. 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
GeneratorCalc is a planning and reference tool. It is not a substitute for ISO 8528 ratings, NFPA 70 / NFPA 110 as adopted locally, the authority having jurisdiction, manufacturer instructions, or the judgment of a licensed installer 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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