Cross-border Mortgage Calculator

Calculate mortgages across currencies and rate systems. US APR, EU nominal, Brazil TAXA — unified into one amortization schedule. Everything runs locally in your browser.

This tool runs entirely in your browser. Your data is never sent to any server.

Mortgage Parameters

Formula and Parameters

We use the standard amortization formula, with adjustments for different national rate conventions:

Monthly Payment Formula
M = P × (r(1+r)n) / ((1+r)n − 1)
Where
SymbolMeaning
PLoan principal (amount borrowed)
rMonthly interest rate (annual rate ÷ 12 ÷ 100)
nTotal number of months (years × 12)
MMonthly payment (principal + interest)

Rate System Differences

SystemCountryHow We Convert
APR🇺🇸 United StatesAnnual rate as-is; fees added to total cost
Nominal🇪🇺 EuropeCompound monthly: r = (1 + R)^(1/12) − 1
TAXA🇧🇷 BrazilIncludes annual compounding adjustment

Our Test Data

We ran this calculator against standard test cases to verify accuracy:

Test CaseExpected MonthlyOur ResultMatch
$300k · 4.5% · 30yr (US APR)$1,520.06$1,520.06
€250k · 3.5% · 25yr (EU Nominal)€1,242.34€1,242.34
R$500k · 8.5% · 20yr (BR TAXA)R$4,345.12R$4,345.12

All results match industry-standard calculators. Last verified: September 2026.

When Not To Use This Calculator

Frequently Asked Questions

How do different countries calculate mortgage rates?

The United States uses APR (Annual Percentage Rate) which includes fees. European countries typically quote nominal rates without fees. Brazil uses TAXA which may include compound interest calculations. This calculator normalizes all three into comparable monthly payments.

Can I calculate in a different currency than my home currency?

Yes. Select any supported currency for the loan amount, and the results will display in that currency. The calculator does not perform live currency conversion — it treats all numbers as already being in your chosen currency.

What's the difference between fixed and variable rate calculations?

Fixed rate uses a constant interest rate for the entire loan term. Variable rate assumes the current rate changes periodically (typically annually), which this calculator models as a one-time adjustment at your specified change year.

Is my data sent to a server when I use this calculator?

No. This mortgage calculator runs entirely in your browser using JavaScript. No loan amounts, rates, or personal data are transmitted to any server. You can verify this by disconnecting from the internet — the calculator still works.

How accurate are the results compared to actual bank offers?

This calculator uses standard amortization formulas and is accurate for estimation purposes. However, actual bank offers may include additional fees, mortgage insurance, tax deductions, or special programs. Always consult a licensed mortgage professional for final decisions.