{"uid":"cap_DQqegzeoiW68O1INXseI9","slug":"sitecheck-finance-loan-calculator-5ee3fb22","name":"SiteCheck Finance Loan Calculator","description":"Loan and investment calculator in exact cents, no outside source. mode=annuity: monthly payment, total interest and the full amortisation schedule (up to 600 months). mode=compound: future value of an initial sum plus monthly contributions. mode=npv or irr: discount or internal rate of return of a list of cashflows (up to 200, the first at time 0). Rates are percentages from 0 to 100 a year (per period for npv and irr); terms up to 50 years.","url":"https://api.sitecheck-api.workers.dev/api/finance/loan?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["mode"],"properties":{"mode":{"type":"string","description":"annuity (default), compound, npv or irr"},"rate":{"type":"string","description":"Annual rate in percent, 0 to 100 (annuity, compound); rate per period in percent for npv (-99 to 1000)"},"cashflows":{"type":"string","description":"Comma-separated cashflows for npv and irr, e.g. -1000,300,400,500 (first at time 0)"},"principal":{"type":"string","description":"Loan amount (annuity) or starting sum (compound), up to two decimals (optional for compound)"},"termYears":{"type":"string","description":"Term in years, up to 50 (annuity, compound)"},"termMonths":{"type":"string","description":"Term in months, 1 to 600, instead of termYears"},"contribution":{"type":"string","description":"Monthly contribution for compound, up to two decimals (optional)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"mode":"annuity","rate":6.5,"months":360,"source":"Computed here in pure code (annuity, monthly compounding, NPV and IRR formulas); no outside source","schedule":[{"month":1,"balance":249774,"payment":1580.17,"interest":1354.17,"principal":226},{"month":2,"balance":249546.77,"payment":1580.17,"interest":1352.94,"principal":227.23},{"month":3,"balance":249318.31,"payment":1580.17,"interest":1351.71,"principal":228.46}],"checkedAt":"2026-10-15T13:40:01.487Z","principal":250000,"totalPaid":568861.58,"disclaimer":"Information only, not financial advice.","lastPayment":1580.55,"totalInterest":318861.58,"monthlyPayment":1580.17}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_RfNfE1NMkyOCWPK1ymmmf","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes loan amortization schedules, compound growth, NPV, and IRR using pure financial math — returning a full month-by-month breakdown of payments, interest, and balance.","exampleAgentPrompt":"Can you calculate the monthly payment and full amortization schedule for a $250,000 annuity loan at 6.5% annual interest over 30 years?","exampleUseCases":[{"title":"Mortgage payment planning","prompt":"I'm buying a house for $400,000 with a 20% down payment. Can you calculate the monthly mortgage payment and total interest I'd pay on a 30-year annuity loan at 7.2% annual interest?"},{"title":"Investment compound growth projection","prompt":"If I invest $15,000 today and add $200 a month, how much will I have after 20 years assuming 7% annual compound growth?"},{"title":"Project IRR evaluation","prompt":"Calculate the IRR for a project where I invest $50,000 upfront and expect cashflows of $10,000, $15,000, $20,000, and $25,000 over the next four years."}],"resultDescription":"A JSON object containing the calculation mode, interest rate, number of months, monthly payment amount, last payment (may differ slightly due to rounding), total paid, total interest, a full month-by-month schedule (each entry with month number, remaining balance, payment, interest portion, and principal portion), a source note confirming pure-code computation, a disclaimer, and a checkedAt timestamp.","failureModes":["Missing required 'mode' parameter returns an error","Invalid or out-of-range rate (e.g. negative or over 100 for annuity) causes a validation error","Conflicting termYears and termMonths parameters may cause unexpected behavior","Cashflows parameter missing for NPV or IRR mode","Principal missing for annuity mode","Term exceeding 50 years or 600 months rejected"],"whenToPreferThis":"Choose this endpoint when you need server-side loan amortization, compound interest projection, NPV, or IRR computation without implementing the math yourself. It is ideal for agents embedded in financial planning, mortgage advisory, or investment analysis workflows. It runs pure-code computation (no external data source) making results reproducible and deterministic. At $0.001 per call it is extremely cost-effective for on-demand financial calculations.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-16T12:40:40.905Z","isFirstParty":false,"canonicalSlug":"sitecheck-finance-loan-calculator-5ee3fb22"}