Python | Convert the decimal number to binary without using library function

Decimal to binary in Python: Here, we are going to learn how to convert the given decimal number to the binary number without using any library function in Python? By IncludeHelp Last updated : January 04, 2024

Problem statement

Given a decimal number and we have to convert it into binary without using library function.

Example

Consider the below example with sample input and output:

Input: 
10

Output: 
1010

Python code to convert decimal to binary

# Python code to convert decimal to binary

# function definition
# it accepts a decimal value 
# and prints the binary value
def decToBin(dec_value):
    # logic to convert decimal to binary 
    # using recursion
    bin_value =''
    if dec_value > 1:
        decToBin(dec_value//2)
    print(dec_value % 2,end = '')

# main code
if __name__ == '__main__':
    # taking input as decimal 
    # and, printing its binary 
    decimal = int(input("Input a decimal number: "))
    print("Binary of the decimal ", decimal, "is: ", end ='')
    decToBin(decimal)

Output

The output of the above example is:

First run:
Input a decimal number: 10
Binary of the decimal  10 is: 1010

Second run:
Input a decimal number: 963
Binary of the decimal  963 is: 1111000011

To understand the above program, you should have the basic knowledge of the following Python topics:

Python Basic Programs »

Python | Convert the binary number to decimal without using library function

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