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California LocalizedGenerated accuracy model review: 2026-05-06

California Commute 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

  • Monthly commute cost = miles per day x commute days per month x fuel or EV cost per mile + parking + tolls + maintenance.

Test cases

Default input regression check

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

Inputs

  • Miles per Day: 38 mi
  • Commute Days per Month: 14
  • Fuel / EV Cost per Mile: 0.18 $/mi
  • Parking per Month: $120
  • Tolls per Month: $65
  • Maintenance per Month: $45

Expected outputs

  • Estimated Monthly Commute Cost: $325.76

Known limitations

  • This is a planning estimate only. It is not DMV, tax, utility, or transportation advice and does not verify official toll schedules, utility tariffs, fuel prices, rebates, parking rules, maintenance needs, or exceptions.

Assumptions

  • Commute miles are round-trip daily miles.
  • Fuel or EV cost per mile is entered by the user.
  • Parking, tolls, and maintenance are monthly planning amounts.

Unit handling

  • Miles per Day accepts values in mi.
  • Commute Days per Month accepts numeric values.
  • Fuel / EV Cost per Mile accepts values in $/mi.
  • Parking per Month accepts values in $.
  • Tolls per Month accepts values in $.
  • Maintenance per Month accepts values in $.
  • Estimated Monthly Commute Cost is displayed as currency.

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 california-commute-cost-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for California Commute 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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