webtaculars / LoanJS

Calculate loan in js (browser/node.js) for equal installments, installments decreasing, the sum of interest, etc.

LoanJS

Super small (~500B) and fast module to calculate loan in js (browser/node.js) for equal/decreasing installments, the sum of interest, etc.

Getting Started

Install the module with:

npm install loanjs

or Bower:

bower install loan-js --save

Calculating Loan:

var LoanJS = require('loanjs');
var loan = new LoanJS.Loan(
  1000, // amount
  12,   // installments number
  5,    // interest rate
  true  // diminishin
);
/** returns
{ 
  installments  : [
    {
      capital     : number,
      interest    : number,
      installment : number,
      remain      : number
    }
  ],
  amount        : number,
  interestSum   : number,
  capitalSum    : number,
  sum           : number
}
*/

Documentation

Loan

LoanJS.Loan(amount, installmentsNumber, interestRate, diminishing)

Arguments

Argument	type	default	Description
amount	number	*required	full amount of Loan
installmentsNumber	number	*required	how meny installments will be
interestRate	number	*required	interest rate in percent (ex. 3.5)
diminishing	bool	false	if installments will be - true: diminishing; false: equal/annuity

Returns

{ 
  installments  : [
    {
      capital     : number,
      interest    : number,
      installment : number,
      remain      : number
    }
  ],
  amount        : number,
  interestSum   : number,
  capitalSum    : number,
  sum           : number
}

Examples

nodejs / browserify example

var Loan = require('loanjs').Loan;

var loan_1 = new Loan(1000, 12, 5, true);
// loan on 1 000($) in 12 diminishing installments (ex. months) with 5% interest rate

var loan_2 = new Loan(500000, 360, 3.5);
// loan on 500 000($) in 360 equal installments (30 years) with 3.5% interest rate

Browser example:

You can also render loan as html table

<script src="../../dist/loan.js"></script>
<script src="../../dist/loanToHtmlTable.js"></script>
<script>
    var loan = new LoanJS.Loan(1000, 12, 5, true);
    
    var div = document.createElement("div");
    div.innerHTML = LoanJS.loanToHtmlTable(loan); // loan rendering as html table string
    document.body.appendChild(div);
</script>

more examples here

Similar projects

• InterestJS - counting regular savings

Contributing

Im open to contributors :).

Release History

2017-08-06 v1.0.0

• go to es6
• make dist files
• make 100% covered tests

2016-02-29 v0.1.4

• update dependencies

2015-10-12 v0.1.3

• fixing typo intrest -> interest #3
• update dependencies

2014-11-10 v0.0.4

• update dependencies

2014-11-10 v0.0.2

• now you can use it in node/browserify and browser

License

Copyright (c) 2014 Grzegorz Klimek
Licensed under the MIT license.