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Home & UtilitiesGenerated accuracy model review: 2026-05-06

Appliance Electricity Cost Calculator accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • Daily kWh = watts / 1000 * hours per day * duty cycle percent / 100. Cost = kWh * electricity rate.

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Appliance Wattage: 1,500 W
  • Hours Used per Day: 4 hr/day
  • Duty Cycle: 100%
  • Electricity Rate Preset: eia_us_residential_average
  • Electricity Rate: 0.18 $/kWh

Expected outputs

  • Monthly Cost: $30.10
  • Daily Cost: $0.99
  • Annual Cost: $360.91
  • Daily Energy Use: 6 kWh

Known limitations

  • This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
  • Use the result as a planning estimate unless the calculator page states a stricter purpose.

Assumptions

  • A 30.4375-day average month is used for monthly cost.
  • Usage and wattage are assumed steady for the entered duty cycle.
  • Calculations run locally and are for planning only.

Unit handling

  • Appliance Wattage accepts values in W.
  • Hours Used per Day accepts values in hr/day.
  • Duty Cycle accepts values in %.
  • Electricity Rate Preset accepts one of the configured options.
  • Electricity Rate accepts values in $/kWh.
  • Monthly Cost is displayed as currency.
  • Daily Cost is displayed as currency.
  • Annual Cost is displayed as currency.
  • Daily Energy Use is displayed in kWh.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.
  • Currency outputs are displayed with standard US dollar formatting.
  • Input precision follows configured step values where provided.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current appliance-electricity-cost-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Appliance Electricity Cost Calculator.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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