Quick guide
How to use this calculator
- Enter the contractual or scenario values requested by each label.
- Keep amounts in one currency and use the whole-period unit shown on each label.
- Review every result with the stated exclusions.
Calculation method
Calculation method
Interest-only payment = principal × nominal annual rate ÷ 12; the unchanged principal then amortizes over the remaining term.
The engine retains calculation precision and rejects invalid or numerically unreliable schedules.
Worked example
Scenario example
On 120,000 at 6%, the interest-only payment is 600 per month. After a 12-month interest-only period, the unchanged 120,000 amortizes over the remaining 108 months.
Interest-only payment = principal × nominal annual rate ÷ 12; the unchanged principal then amortizes over the remaining term.
Supported inputs
Precision and limits
Visible limits
Amounts are capped at 1e12, entered rates at 1000%, periods at 1,200 months or 100 years, and fixed decimals at 12 places. A derived ARM rate above 1000% is rejected.
International scope
No jurisdiction, currency, tax, insurance, index path, lender rule, or legal interpretation is assumed.
Not a quotation
Results are mathematical scenarios based only on entered terms.
Specific assumptions
The model assumes no principal payments during the interest-only period and a constant entered rate.