I need help to use pluguim bigmoney.js

Include the plugin

You must first include the plugin and particularly the bigmoney-all.js :

<script src="bigmoney-all.js"></script>

If you are working with Node JS, you can do this at the cost of require('bigmoney') , as long as you first place it in the node_modules folder.

Configuring conversions

Then you can set the various currencies available as well as your conversion rates if you want to be able to convert between currencies:

Money.settings = {
    base: "BRL",
    rates: {
        BRL : 1, //Esta é a base, as outras são calculadas convertendo a partir desta
        USD: 0.31,
        EUR: 0.25
    },
    format: "%decimal %currency"
}

With special attention that the conversions that I put refer the day this answer was published.

Conversions are made by calling the convert method passing the currency you want to convert to:

dinheiro.convert('USD'); //obter o resultado da conversão para dólar americano

Create money

Now each time you want to work with the currency, just create a new object with Money() and specify the currency:

let dinheiro = Money(325, "BRL");

Available operations

If you want to operate on this money you can use the various arithmetic operators available from the library:

• plus - add
• minus - subtract
• times - multiply
• div - divide
• mod - rest of the division

Remembering that each operation returns the new result.

Now let's look at an example where we calculated and added 10% of $ 325:

let dinheiro = Money(325, "BRL");
dinheiro = dinheiro.plus(dinheiro.div(10)); //dinheiro soma com dinheiro a dividir por 10
console.log(dinheiro.valueOf()) //357.5

At any time you want to know the value that the variable has just use the method valueOf .

Formatting

To show specifying a format you must use the format method:

console.log(dinheiro.format("R$ %decimal")); //mostra R$ 357.5

You can even set the currency format to simplify later formatting at the expense of formatter :

Money.formatter = function(decimal, currency, formatParam) {
    switch(currency) {
        case 'USD': return "$" + decimal;
        case 'EUR': return "€" + decimal;
        case 'JPY': return "¥" + decimal;
        case 'BRL': return "R$ " + decimal;
        default: return decimal + " " + currency;
    }
};

Now if you have money in the real format, just show calling format with no parameters:

let dinheiro = Money(100, "BRL");
console.log(dinheiro.format()); //mostra R$ 100

You can even use the formatting available at Number.toLocaleString to simplify and stay closer to the one you use day by day:

Money.formatter = function(decimal, currency, formatParam) {
    switch(currency) {
        case 'USD': return "$" + decimal;
        case 'EUR': return "€" + decimal;
        case 'JPY': return "¥" + decimal;
        case 'BRL': return decimal.toLocaleString('pt-br',{style: 'currency', currency: 'BRL'});
        default: return decimal + " " + currency;
    }
};

let dinheiro = Money(100, "BRL");
console.log(dinheiro.format()); //mostra R$100,00