BigInt

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BigInt , 253 - 1, , JavaScript Number . , Number.MAX_SAFE_INTEGER.

const theBiggestInt = 9007199254740991n;

const alsoHuge = BigInt(9007199254740991);
//  9007199254740991n

const hugeString = BigInt("9007199254740991");
//  9007199254740991n

const hugeHex = BigInt("0x1fffffffffffff");
//  9007199254740991n

const hugeBin = BigInt(
  "0b11111111111111111111111111111111111111111111111111111",
);
//  9007199254740991n

Number, Math Number.

: Number BigInt .

, BigInt (Number).

typeof, BigInt "bigint":

typeof 1n === "bigint"; // true
typeof BigInt("1") === "bigint"; // true

, BigInt :

typeof Object(1n) === "object"; // true

BigInt ( - BigInt): +, *, -, **, %.

, >>> ( ).

(+) asm.js.

const previousMaxSafe = BigInt(Number.MAX_SAFE_INTEGER);
//  9007199254740991n

const maxPlusOne = previousMaxSafe + 1n;
//  9007199254740992n

const theFuture = previousMaxSafe + 2n;
//  9007199254740993n,  !

const multi = previousMaxSafe * 2n;
//  18014398509481982n

const subtr = multi  10n;
//  18014398509481972n

const mod = multi % 10n;
//  2n

const bigN = 2n ** 54n;
//  18014398509481984n

bigN * -1n
//  18014398509481984n

/ , , . , BigInt, , - .

: BigInt.

const expected = 4n / 2n;
//  2n

const rounded = 5n / 2n;
//  2n, not 2.5n

BigInt Number .

0n === 0;
//  false

0n == 0;
//  true

BigInt .

1n < 2;
//  true

2n > 1;
//  true

2 > 2;
//  false

2n > 2;
//  false

2n >= 2;
//  true

const mixed = [4n, 6, -12n, 10, 4, 0, 0n];
//   [4n, 6, -12n, 10, 4, 0, 0n]

mixed.sort();
//  [-12n, 0, 0n, 10, 4n, 4, 6]

, - BigInt , :

0n === Object(0n); // false
Object(0n) === Object(0n); // false

const o = Object(0n);
o === o; // true

BigInt :

if (0n) {
  console.log("  if!");
} else {
  console.log("  else!");
}

//  "  else!"

0n || 12n;
//  12n

0n && 12n;
//  0n

Boolean(0n);
//  false

Boolean(12n);
//  true

!12n;
//  false

!0n;
//  true

BigInt(): BigInt.

BigInt.asIntN(): BigInt -2width-1 2width-1-1
BigInt.asUintN(): a BigInt 0 2width-1

BigInt.prototype.toLocaleString(): . Object.prototype.toLocaleString().
BigInt.prototype.toString(): , . Object.prototype.toString().
BigInt.prototype.valueOf(): . Object.prototype.valueOf().

Number BigInt , BigInt , , 253 .

BigInt . BigInt .

JSON

JSON.stringify() BigInt TypeError, BigInt JSON , toJSON, :

BigInt.prototype.toJSON = function () {
  return this.toString();
};

, JSON.stringify :

JSON.stringify(BigInt(1));
// '"1"'

//  true,  BigInt   
function isPrime(p) {
  for (let i = 2n; i * i <= p; i++) {
    if (p % i === 0n) return false;
  }
  return true;
}

//  BigInt      BigInt
function nthPrime(nth) {
  let maybePrime = 2n;
  let prime = 0n;

  while (nth >= 0n) {
    if (isPrime(maybePrime)) {
      nth--;
      prime = maybePrime;
    }
    maybePrime++;
  }

  return prime;
}

nthPrime(20n);
//  73n

Specification
ECMAScript 2027 LanguageSpecification # sec-bigint-objects

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This page was last modified on 29 . 2026 . by MDN contributors.

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