# How to Convert a Binary String to an Integer in Python?

In Python, you can use the `int()` method (with a base `2` as the second argument) to convert a binary string to its integer equivalent, for example, like so:

```num = int('11000000111001', 2)

print(num) #=> 12345
```

This also works with binary strings that have the "`0b`" (or "`0B`") binary radix prefix:

```# Python 2.6+
num = int('0b11000000111001', 2)

print(num) #=> 12345
```
```# Python 2.6+
num = int('0B11000000111001', 2)

print(num) #=> 12345
```

Specifying an invalid binary number would raise the following error:

```// ValueError: invalid literal for int() with base 2: '0o11111'
int('0o11111', 2)
```

If the binary string has `0b` (or `0B`) radix prefix, then you may also specify `0` as the second argument (i.e. the base) to the `int()` method, which would make it infer the value:

```# Python 2.6+
num = int('0b11000000111001', 0)

print(num) #=> 12345
```

This could be useful, for example, if a variable with a number can be of different types (such as binary, octal, hexadecimal, etc.).

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