BigInteger bitLength() Method in Java (original) (raw)

Last Updated : 24 Mar, 2025

The **java.math.BigInteger.bitLength() method returns the number of bits in the minimal two's-complement representation of this BigInteger, excluding a sign bit. For positive BigIntegers, this is equivalent to the number of bits in the ordinary binary representation. The bitLength method Computes (ceil(log2(this < 0 ? -this : this+1))).
**Syntax:

public int bitLength()

**Parameters: The method does not take any parameters.
**Return Value: The method is used to return the number of bits in the minimal two’s-complement representation of this BigInteger, excluding a sign bit.
**Examples:

Input: value = 2300
Output: 12
**Explanation:
Binary signed 2's complement of 2300 = 0000100011111100
first four bits are signed bit so exclude them than remaining
no of bits = 12. So bitLength in 0000100011111100 = 12.

Input: value = 5482549
Output: 23

The below program illustrates the use of the bitLength() method of BigInteger.

Java `

// Program to demonstrate bitLength() method of BigInteger

import java.math.*;

public class GFG {

public static void main(String[] args)
{

    // Create  BigInteger objects
    BigInteger biginteger = new BigInteger("2300");

    // Call bitLength() method on bigInteger
    int count = biginteger.bitLength();

    String result = "bitLength of  " + biginteger +
    " is " + count;

    // Print result
    System.out.println(result);
}

}

`

Output

bitLength of 2300 is 12