# Python Program to Convert Binary Number to Decimal and vice-versa

In this python tutorial, you will learn how to Convert Binary Number to Decimal and vice-versa with the if statement and built in functions of the python programming language.

## How to Convert Binary Number to Decimal and vice-versa?

Let’s take a look at the first source code, here the values are assigned in the code, the if statement and built in functions carry out the function.

BINARY TO DECIMAL

```#Python Program to Convert Binary Number to Decimal

def binaryToDecimal(n):
return int(n,2)

if __name__ == '__main__':
print(binaryToDecimal('110'))
print(binaryToDecimal('10000'))
print(binaryToDecimal('101'))
```

OUTPUT:

```6
16
5```
1. At the start, we use `def binaryToDecimal(n):` where the `def` keyword is used to define a function and the `binaryToDecimal`  is used to call the function to get the value of the variable `n`.
2. After that we return the integer value of the variable `n`  in `int(n,2)` using the `return` function .
3. The code `if __name__ == '__main__':` is used to execute some code only if the file was run directly, and not imported, with the condition satisfied it moves to the next step.
4. Using the `binaryToDecimal` function we find the Decimal form of the binary value assigned in the code using the built in function, we display the final values using the `print` function.

Let’s take a look at the first second code , here the values are assigned in the code, the if statement and built in functions carry out the function.

DECIMAL TO BINARY

```# Python Program to Convert Decimal Number to Binary

def decimalToBinary(n):
return bin(n).replace("0b","")

if __name__ == '__main__':
print(decimalToBinary(6))
print(decimalToBinary(16))
print(decimalToBinary(5))
```

OUTPUT:

```110
10000
101```
1. At the start, we use `def decimalToBinary(n):` where the `def` keyword is used to define a function and the `decimalToBinary`  is used to call the function to get the value of the variable `n`.
2. After that we return the Binary value of the variable `n` using the function `return` followed by the `replace` function which is used to replace the values `("0b","")` with another value.
3. The code `if __name__ == '__main__':` is used to execute some code only if the file was run directly, and not imported, with the condition satisfied it moves to the next step.
4. Using the `decimalToBinary` function we find the Binary form of the Decimal value assigned in the code using the built in function, we display the final values using the `print` function.

NOTE:

• The replace() function is an inbuilt function in the Python programming language that returns a copy of the string where all occurrences of a substring are replaced with another substring.
• The if  statement evaluates whether an expression is true. If a condition is true, the “if” statement executes.
• The colon : at the end of the if and else statement tells Python that the next line of code should only be run if the condition is true.
• The bin() function  is used to convert from a decimal value to its corresponding binary value.
•  The int() function to convert a binary to its decimal value.
• The print() function prints the specified message to the screen, or other standard output device.