Python String Methods

What Are String Methods?

A string method is a built-in operation that allows you to perform a specific task on a string.

Python provides many useful methods for working with text, including methods for changing case, searching, replacing, splitting, joining, and validating strings.

string.method()

name = "python"

print(name.upper())

PYTHON

lower() & upper()

The lower() method converts letters to lowercase, while upper() converts letters to uppercase.

text = "Hello Python"

print(text.lower())
print(text.upper())

hello python
HELLO PYTHON

These methods are particularly useful when comparing text without worrying about uppercase or lowercase differences.

answer = "YES"

if answer.lower() == "yes":
    print("Confirmed")

capitalize() & title()

capitalize() makes the first character uppercase and converts the remaining characters to lowercase.

title() converts the first character of each word to uppercase.

text = "python programming language"

print(text.capitalize())
print(text.title())

Python programming language
Python Programming Language

swapcase()

The swapcase() method changes uppercase letters to lowercase and lowercase letters to uppercase.

text = "PyThOn"

print(text.swapcase())

pYtHoN

strip()

The strip() method removes leading and trailing whitespace from a string.

name = "   Adnan   "

clean_name = name.strip()

print(clean_name)

Adnan

lstrip() & rstrip()

lstrip() removes whitespace from the left side, while rstrip() removes whitespace from the right side.

text = "   Python   "

print(text.lstrip())
print(text.rstrip())

Python   
   Python

replace()

The replace() method replaces one piece of text with another.

text = "I like Java"

new_text = text.replace("Java", "Python")

print(new_text)

I like Python

You can also specify how many occurrences should be replaced.

text = "cat cat cat"

print(text.replace("cat", "dog", 2))

dog dog cat

find()

The find() method searches for a substring and returns the index of its first occurrence.

text = "I love Python"

position = text.find("Python")

print(position)

7

If the substring cannot be found, find() returns -1.

text = "Python"

print(text.find("Java"))

-1

index()

The index() method also searches for a substring and returns its position.

text = "I love Python"

print(text.index("Python"))

7

count()

The count() method tells you how many times a substring appears in a string.

text = "banana"

print(text.count("a"))
print(text.count("an"))

3
2

startswith() & endswith()

These methods check whether a string starts or ends with a particular piece of text.

filename = "report.pdf"

print(filename.startswith("report"))
print(filename.endswith(".pdf"))

True
True

These methods are extremely useful when validating filenames, URLs, usernames, and other text patterns.

split()

The split() method divides a string into a list of smaller strings.

sentence = "Python is easy to learn"

words = sentence.split()

print(words)

['Python', 'is', 'easy', 'to', 'learn']

By default, whitespace is used as the separator. You can also provide your own separator.

data = "Ali,25,Multan"

parts = data.split(",")

print(parts)

['Ali', '25', 'Multan']

join()

The join() method does the opposite of split(): it combines strings from an iterable into one string.

words = ["Python", "is", "powerful"]

sentence = " ".join(words)

print(sentence)

Python is powerful

The string before .join() becomes the separator.

items = ["Python", "HTML", "CSS"]

print(", ".join(items))
print(" | ".join(items))
print("-".join(items))

Python, HTML, CSS
Python | HTML | CSS
Python-HTML-CSS