JS BigInt.asUintN()

The BigInt.asUintN static method is used to wrap a BigInt value to an unsigned integer between between 0 and 2width-1.

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Syntax

BigInt.asUintN(width, bigint);

Parameters

width

The amount of bits available for the integer size.

bigint

The integer to clamp to fit into the supplied bits.

Returns

The value of bigint modulo 2width as an unsigned integer.

Examples

Staying in 64-bit ranges

The BigInt.asUintN() method can be useful to stay in the range of 64-bit arithmetic.

const max = 2n ** 64n - 1n;
BigInt.asUintN(64, max);
// ↪ 18446744073709551615n
BigInt.asUintN(64, max + 1n);
// ↪ 0n
// zero because of overflow

Specifications

See also

• BigInt
• BigInt.asIntN()