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Finance & LoansGenerated accuracy model review: 2026-05-06
Debt Payoff 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
- The calculator pays the minimum on all debts. Any remaining budget is applied as an extra payment to Debt 1 (smallest balance). Once Debt 1 is gone, its payment + extra is rolled over to Debt 2, creating a snowball effect.
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Monthly Payment Budget: $1,000
- Debt 1 Balance: $5,000
- Debt 1 Rate: 18%
- Debt 1 Minimum: $100
- Debt 2 Balance: $2,000
- Debt 2 Rate: 22%
- Debt 2 Minimum: $50
- Debt 3 Balance: $0
- Debt 3 Rate: 0%
- Debt 3 Minimum: $0
Expected outputs
- Time to Debt Free: 0y 9m
- Total Interest Paid: $516.65
Known limitations
- Currently limited to 3 debts and fixed minimum payments. Assumes Snowball ordering (Debt 1 is target).
Assumptions
- Inputs are interpreted exactly as entered in the calculator form.
- The calculation runs locally in the browser using the current checked-in calculator definition.
Unit handling
- Monthly Payment Budget accepts values in $.
- Debt 1 Balance accepts values in $.
- Debt 1 Rate accepts values in %.
- Debt 1 Minimum accepts values in $.
- Debt 2 Balance accepts values in $.
- Debt 2 Rate accepts values in %.
- Debt 2 Minimum accepts values in $.
- Debt 3 Balance accepts values in $.
- Debt 3 Rate accepts values in %.
- Debt 3 Minimum accepts values in $.
- Total Interest Paid 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.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current debt-payoff-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for Debt Payoff.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.