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Finance & LoansGenerated accuracy model review: 2026-05-06
CD 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
- CDs use compound interest. This calculator uses the formula A = P(1 + r/n)^(nt), assuming monthly compounding which is standard for most consumer CDs.
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Deposit Amount: $10,000
- APY: 4.5%
- Term (Months): 12
Expected outputs
- Total at Maturity: $10,459.40
- Interest Earned: $459.40
Known limitations
- Assumes earnings are reinvested into the CD (compounded), not withdrawn monthly.
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
- Deposit Amount accepts values in $.
- APY accepts values in %.
- Term (Months) accepts numeric values.
- Total at Maturity is displayed as currency.
- Interest Earned 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 cd-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for CD Calculator.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.