ThetoString() method ofBigInt values returns a string representing the specifiedBigInt value. The trailing "n" is not part of the string.

Try it

console.log(1024n.toString());// Expected output: "1024"console.log(1024n.toString(2));// Expected output: "10000000000"console.log(1024n.toString(16));// Expected output: "400"

Syntax

toString()toString(radix)

Parameters

radixOptional

An integer in the range 2 through 36 specifying the base to use for representing the BigInt value. Defaults to 10.

Return value

A string representing the specifiedBigInt value.

Exceptions

RangeError

Thrown ifradix is less than 2 or greater than 36.

Description

TheBigInt object overrides thetoString method ofObject; it does not inheritObject.prototype.toString(). ForBigInt values, thetoString() method returns a string representation of the value in the specified radix.

For radixes above 10, the letters of the alphabet indicate digits greater than 9. For example, for hexadecimal numbers (base 16)a throughf are used.

If the specified BigInt value is negative, the sign is preserved. This is the case even if the radix is 2; the string returned is the positive binary representation of the BigInt value preceded by a- sign,not the two's complement of the BigInt value.

ThetoString() method requires itsthis value to be aBigInt primitive or wrapper object. It throws aTypeError for otherthis values without attempting to coerce them to BigInt values.

BecauseBigInt doesn't have a[Symbol.toPrimitive]() method, JavaScript calls thetoString() method automatically when aBigIntobject is used in a context expecting a string, such as in atemplate literal. However, BigIntprimitive values do not consult thetoString() method to becoerced to strings — rather, they are directly converted using the same algorithm as the initialtoString() implementation.

BigInt.prototype.toString = () => "Overridden";console.log(`${1n}`); // "1"console.log(`${Object(1n)}`); // "Overridden"

Examples

Using toString()

17n.toString(); // "17"66n.toString(2); // "1000010"254n.toString(16); // "fe"(-10n).toString(2); // "-1010"(-0xffn).toString(2); // "-11111111"

Negative-zero BigInt

There is no negative-zeroBigInt as there are no negative zeros in integers.-0.0 is an IEEE floating-point concept that only appears in the JavaScriptNumber type.

(-0n).toString(); // "0"BigInt(-0).toString(); // "0"

Specifications

Browser compatibility

See also

• BigInt.prototype.toLocaleString()
• BigInt.prototype.valueOf()
• Number.prototype.toString()