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Medical BillingGenerated accuracy model review: 2026-05-06

Deductible, Coinsurance, Copay Split 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

  • Patient responsibility = deductible applied + ((allowed amount - deductible applied) * coinsurance percent) + copay. Plan payment = allowed amount - patient responsibility, floored at zero.

Test cases

Default input regression check

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

Inputs

  • Allowed Amount: $800
  • Deductible Remaining: $300
  • Coinsurance: 20%
  • Copay: $25

Expected outputs

  • Patient Responsibility: $425.00
  • Deductible Applied: $300.00
  • Coinsurance Amount: $100.00
  • Estimated Plan Payment: $375.00

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

  • Copay is added after deductible and coinsurance in this simple model.
  • The calculator does not enforce out-of-pocket maximums or plan exclusions.
  • Values remain local.

Unit handling

  • Allowed Amount accepts values in $.
  • Deductible Remaining accepts values in $.
  • Coinsurance accepts values in %.
  • Copay accepts values in $.
  • Patient Responsibility is displayed as currency.
  • Deductible Applied is displayed as currency.
  • Coinsurance Amount is displayed as currency.
  • Estimated Plan Payment 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 deductible-coinsurance-copay-split-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Deductible, Coinsurance, Copay Split 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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