Python slice string with Example

Python string supports slicing to create substring. Note that Python string is immutable, slicing creates a new substring from the source string and original string remains unchanged.

Python slice string

Python slice string syntax is:

The slicing starts with the start_pos index (included) and ends at end_pos index (excluded). The step parameter is used to specify the steps to take from start to end index.

Python String slicing always follows this rule: s[:i] + s[i:] == s for any index ‘i’.

All these parameters are optional – start_pos default value is 0, the end_pos default value is the length of string and step default value is 1.

Let’s look at some simple examples of string slice function to create substring.

Output:

Note that since none of the slicing parameters were provided, the substring is equal to the original string.

Let’s look at some more examples of slicing a string.

Output:

Note that index value starts from 0, so start_pos 2 refers to the third character in the string.

Reverse a String using Slicing

We can reverse a string using slicing by providing the step value as -1.

Output: dlroWolleH

Let’s look at some other examples of using steps and negative index values.

Output: loo

Here the substring contains characters from indexes 2,4 and 6.

Output: lroWoll

Here the index values are taken from end to start. The substring is made from indexes 1 to 7 from end to start.

Python slice string

Output: lool

Python slice string

Python slice works with negative indexes too, in that case, the start_pos is excluded and end_pos is included in the substring.

Output: or

Python slice string

Python string slicing handles out of range indexes gracefully.

That’s all for python string slice function to create substring.

You can checkout complete python script and more Python examples from our GitHub Repository.

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