Convert hex string to integer in Python

Question

How do I convert a hex string to an integer? ``` "0xffff" ⟶ 65535 "ffff" ⟶ 65535 ```

Accepted Answer

Without the `0x` prefix, you need to specify the base explicitly, otherwise there's no way to tell:

```
x = int("deadbeef", 16)
```

With the `0x` prefix, Python can distinguish hex and decimal automatically:

```
>>> print(int("0xdeadbeef", 0))
3735928559
>>> print(int("10", 0))
10
```

(You must specify `0` as the base in order to invoke this prefix-guessing behavior; if you omit the second parameter, `int()` will assume base-10.)

Solution