Python Math: Convert a binary number to decimal number

Last update on April 24 2025 12:35:13 (UTC/GMT +8 hours)

31. Decimal to Binary Converter

Write a Python program to convert a decimal number to a binary number.

Sample Solution:

Python Code:

b_num = list(input("Input a binary number: "))
value = 0

for i in range(len(b_num)):
	digit = b_num.pop()
	if digit == '1':
		value = value + pow(2, i)
print("The decimal value of the number is", value)

Sample Output:

Input a binary number: 1000001                                                                                
The decimal value of the number is 65

Pictorial Presentation:

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to convert a given decimal number to binary without using the built-in bin() function, and then print the binary string.
• Write a Python function that accepts a decimal number, converts it to binary using recursion, and returns the binary representation as a string.
• Write a Python script to read a decimal number from the user, convert it to binary using iterative division, and display the result.
• Write a Python program to compare the binary conversion of a decimal number using a custom algorithm versus the built-in bin() function.

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Python Code Editor:

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