Python String find()

In this tutorial, we will learn about the Python String find() method with the help of examples.

The find() method returns the index of first occurrence of the substring (if found). If not found, it returns -1.

Example

message = 'Python is a fun programming language'

# check the index of 'fun'
print(message.find('fun'))

# Output: 12

1. Syntax of String find()

The syntax of the find() method is:

str.find(sub[, start[, end]] )

2. find() Parameters

The find() method takes maximum of three parameters:

  • sub – It is the substring to be searched in the str string.
  • start and end (optional) – The range str[start:end] within which substring is searched.

3. find() Return Value

The find() method returns an integer value:

  • If the substring exists inside the string, it returns the index of the first occurence of the substring.
  • If a substring doesn’t exist inside the string, it returns -1.

4. Working of find() method

How find() and rfind() works in Python?
Working of Python string’s find() and rfind() methods

5. Example 1: find() With No start and end Argument

quote = 'Let it be, let it be, let it be'

# first occurance of 'let it'(case sensitive)
result = quote.find('let it')
print("Substring 'let it':", result)

# find returns -1 if substring not found
result = quote.find('small')
print("Substring 'small ':", result)

# How to use find()
if (quote.find('be,') != -1):
    print("Contains substring 'be,'")
else:
    print("Doesn't contain substring")

Output

Substring 'let it': 11
Substring 'small ': -1
Contains substring 'be,'

6. Example 2: find() With start and end Arguments

quote = 'Do small things with great love'

# Substring is searched in 'hings with great love'
print(quote.find('small things', 10))

# Substring is searched in ' small things with great love' 
print(quote.find('small things', 2))

# Substring is searched in 'hings with great lov'
print(quote.find('o small ', 10, -1))

# Substring is searched in 'll things with'
print(quote.find('things ', 6, 20))

Output

-1
3
-1
9

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