Finance Math API
Loan & mortgage payments, amortization, compound interest, ROI, VAT, tip, and break‑even.
Get it on RapidAPI ↗Finance Math is a stateless API for the everyday financial calculations apps need: loan and mortgage monthly payments, full amortization schedules, compound interest with optional recurring contributions, return on investment (with annualized ROI), VAT (add or extract), tip splitting, and break-even analysis.
Every endpoint is a pure formula — send the inputs as query parameters, get clean numeric JSON back, rounded to cents. No data is stored. Ideal for budgeting tools, loan and mortgage calculators, e-commerce pricing, invoicing, and finance dashboards.
Endpoints
| Method | Path | Description |
|---|---|---|
| GET | /loan | monthly payment |
| GET | /amortization | schedule |
| GET | /compound-interest | compound interest |
| GET | /roi | ROI |
| GET | /vat | VAT |
| GET | /tip | tip |
| GET | /breakeven | break‑even |
Quick start
curl --request curl \
--url 'https://finance-math.p.rapidapi.com/-G "https://finance-math.p.rapidapi.com/loan" -d "principal=250000" -d "annualRate=3.5" -d "termMonths=360" -H "X-RapidAPI-Key: YOUR_KEY" -H "X-RapidAPI-Host: finance-math.p.rapidapi.com"' \
--header 'X-RapidAPI-Key: YOUR_KEY' \
--header 'X-RapidAPI-Host: finance-math.p.rapidapi.com' \
--header 'content-type: application/json' \
--data '{}'const res = await fetch('https://finance-math.p.rapidapi.com/-G "https://finance-math.p.rapidapi.com/loan" -d "principal=250000" -d "annualRate=3.5" -d "termMonths=360" -H "X-RapidAPI-Key: YOUR_KEY" -H "X-RapidAPI-Host: finance-math.p.rapidapi.com"', {
method: 'curl',
headers: {
'X-RapidAPI-Key': 'YOUR_KEY',
'X-RapidAPI-Host': 'finance-math.p.rapidapi.com',
'content-type': 'application/json'
},
body: JSON.stringify({})
});
const data = await res.json();{
"monthlyPayment": 1122.61,
"totalPaid": 404140.22,
"totalInterest": 154140.22
}Pricing
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Frequently asked questions
Does it handle different currencies?
Values are numeric; currency symbols are up to the client.
Is the calculation precise?
Uses double‑precision floating point, sufficient for typical finance needs.
Any data storage?
No, all calculations are stateless.
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