5 Integration Channels

PropCalc — Developer Ecosystem

Integrate multi-country real estate calculations into your projects. Embeddable widget, REST API, npm package, Chrome extension, Google Sheets add-on.

API Documentation →npm install @tevaxia/propcalc

10 countries · 16 functions · MIT · By Tevaxia

Channels

Countries

Functions

Free calls/month

Dependencies

Embeddable Widget

Three lines of code to add PropCalc to any website. No dependencies, no framework required.

<link rel="stylesheet"
      href="https://www.tevaxia.lu/propcalc/propcalc.min.css">

<script src="https://www.tevaxia.lu/propcalc/propcalc.min.js"></script>

<div data-propcalc data-country="lu" data-lang="en"></div>

Configuration attributes

data-countryISO 3166-1 alpha-2 country code (lu, fr, de, gb, be, es, pt, it, nl, us)

data-langInterface language (fr, en, de, es, pt, it, nl, lb)

data-moduleModules to display: fees, borrowing, yield, cashflow, comparator, prequalify, amortization, buyvsrent, scenarios, transfertax

data-themeVisual theme: light (default) or dark

data-accent-colorAny valid CSS accent color (#1a365d, rgb(...), hsl(...))

Free · Tevaxia credit shown · Zero dependencies

REST API

Base URL: https://www.tevaxia.lu/api/v1/propcalc

1,000 free calls/month · CORS enabled · JSON

Method	Endpoint	Description
POST	/fees	Acquisition fees (notary, duties, taxes)
POST	/mortgage	Borrowing capacity and monthly payments
POST	/yield	Gross, net, and net-net rental yield
POST	/cashflow	Monthly investor cash-flow
GET	/countries	List of supported countries with metadata

Example: acquisition fees calculation

curl -X POST https://www.tevaxia.lu/api/v1/propcalc/fees \
  -H "Content-Type: application/json" \
  -d '{
    "country": "lu",
    "price": 700000,
    "type": "existing"
  }'

npm Package

All calculation logic in a single package. Zero dependencies, tree-shakable, native TypeScript.

npm install @tevaxia/propcalc

import { calculateAcquisitionFees, getCountryData } from '@tevaxia/propcalc';

const lu = getCountryData('lu');
const fees = calculateAcquisitionFees({ countryData: lu, price: 700000 });

console.log(fees.total);        // 49 000
console.log(fees.notaryFees);   // 7 000
console.log(fees.transferTax);  // 42 000

Functions

Countries

MIT

License

Dependencies

Chrome Extension

Instant calculations on property listing websites. Automatic price detection, 3 tabs: Fees, Yield, Mortgage.

Supported portals

atHome.lu

ImmoScout24

Idealista

Rightmove

SeLoger

LeBonCoin

Funda

Zillow

Install from Chrome Web Store →

Automatic price detection · 3 tabs: Fees, Yield, Mortgage

Google Sheets Add-on

Right inside your spreadsheets. 10 countries, regional granularity.

=PROPCALC_FEES(price, country, region)Full acquisition fees breakdown

=PROPCALC_MORTGAGE(income, expenses, country)Maximum borrowing capacity

=PROPCALC_YIELD(price, rent, expenses, country)Net rental yield

=PROPCALC_CAPACITY(price, deposit, rate, term)Monthly payment and total cost

=PROPCALC_TAX_RATE(price, country, region)Effective transfer tax rate

Right in your spreadsheets · 10 countries · Regional granularity

Ready to integrate PropCalc?

Pick the channel that fits your stack. Widget, API, npm, Chrome, or Sheets — all free to get started.

PropCalc — Main page →tevaxia.lu

Chargement...

<link rel="stylesheet" href="https://www.tevaxia.lu/propcalc/propcalc.min.css"> <script src="https://www.tevaxia.lu/propcalc/propcalc.min.js"></script> <div data-propcalc data-country="lu" data-lang="en"></div>

Method

Endpoint

POST

/fees

POST

/mortgage

POST

/yield

POST

/cashflow

GET

/countries

import { calculateAcquisitionFees, getCountryData } from '@tevaxia/propcalc'; const lu = getCountryData('lu'); const fees = calculateAcquisitionFees({ countryData: lu, price: 700000 }); console.log(fees.total); // 49 000 console.log(fees.notaryFees); // 7 000 console.log(fees.transferTax); // 42 000