Python String find() method

Python String find()

Python String.find() method returns the index of first occurrence of specified value in given string.

If the value is not present in this string, find() returns -1.

In this tutorial, we will learn the syntax and examples for find() method of String class.

Syntax

The syntax of String find() method in Python is

str.find(value, start, end)

where

Parameter	Required/ Optional	Description
value	Required	A string. Index of this value in the string has to be returned.
start	Optional	An integer. The index from which, the value has to be searched in this string.
end	Optional	An integer. The index until which, the value has to be searched in this string.

Examples

find() with default values

In this example, we will take a string 'abcd-abcd-abcd', and find the index of the value 'bc' in the string.

Example.py

x = 'abcd-abcd-abcd'
value = 'cd'
result = x.find(value)
print("Index :", result)

Output

Index : 2

Explanation

'a b c d - a b c d - a b c d'
 0 1 2 3 4 5 6 7 8 9 10 . . 
     c d                       : index of 'cd' is 2

The index of first occurrence of value is 2.

Even though there are multiple occurrences of the value in this string, find() method returns only the index of first occurrence.

find() with Specific Start

In the following program, we will specify a starting position/index from which the search for the value value in the string has to happen.

Example.py

x = 'abcd-abcd-abcd'
value = 'cd'
start = 5
result = x.find(value, start)
print("Index :", result)

Output

Index : 7

Explanation

'a b c d - a b c d - a b c d'
 0 1 2 3 4 5 6 7 8 9 10 . . 
           |
           start=5 from this position
               c d          : index of 'cd' is 7

find() with Specific Start and End

In the following program, we will specify a starting position/index from which the search for the value value in the string has to happen and the end position up until which the search for value in the string has to happen.

Example.py

x = 'abcd-abcd-abcd'
value = 'cd'
start = 5
end = 7
result = x.find(value, start, end)
print("Index :", result)

Output

Index : -1

Explanation

'a  b  c  d  -  a  b  c  d  -  a  b  c  d'
 0  1  2  3  4  5  6  7  8  9 10 11 12 13
                |     |
          start=5     end=7

There is no occurrence of the value in this string for given start and end values.

Conclusion

In this Python Tutorial, we learned how to find the index of first occurrence of specified value in given string, using String method – find().