BigInteger

Yet another BigInteger class in JavaScript This library performs arithmetic operations on integers of arbitrary size.

To use it from a web browser:

<script src="BigInteger.js"></script>

To use it from the node.js:

npm install js-big-integer

Then:

var BigInteger = require("BigInteger").BigInteger;

The API is terrible, but small integers are stored as primitive numbers, so operations on small integers are faster.

`BigInteger`	`Number`	`BigInt` (https://github.com/tc39/proposal-bigint)
`BigInteger.parseInt(string, radix)`	`Number.parseInt(string, radix)`	`BigInt(radix === 16 ? "0x" + string : string)`
`BigInteger.compareTo(a, b)`	`Math.sign(a - b)`	`a < b ? -1 : (b < a ? +1 : 0)`
`BigInteger.negate(a)`	`0 - a`	`-a`
`BigInteger.add(a, b)`	`a + b`	`a + b`
`BigInteger.subtract(a, b)`	`a - b`	`a - b`
`BigInteger.multiply(a, b)`	`0 + a * b`	`a * b`
`BigInteger.divide(a, b)`	`0 + Math.trunc(a / b)`	`a / b`
`BigInteger.remainder(a, b)`	`0 + a % b`	`a % b`
`a.toString(radix)`	`a.toString(radix)`	`a.toString(radix)`

Example

var factorial = function (n) {
  var result = BigInteger.parseInt("1", 10);
  var i = 0;
  while (++i <= n) {
    result = BigInteger.multiply(result, BigInteger.parseInt(i.toString(), 10));
  }
  return result;
};

console.log(factorial(30).toString(10));

Other pure JavaScript implementations:

Benchmark: http://yaffle.github.io/BigInteger/benchmark/

TGM/BigInteger

BigInteger

Example