Useful String Methods

What is a method?

A method is a function that belongs to a value. You use it with a dot: text.upper(). String methods give you a new string and leave the original unchanged.

Changing case

text = "Hello World"
print(text.upper())
print(text.lower())
print(text.title())
print(text.swapcase())

Output

HELLO WORLD
hello world
Hello World
hELLO wORLD

Removing extra spaces

strip() removes spaces from both ends. Great for cleaning up what users type:

messy = "    hello    "
print("[" + messy + "]")
print("[" + messy.strip() + "]")

Output

[    hello    ]
[hello]

Replacing text

sentence = "I like cats. Cats are cute."
print(sentence.replace("cats", "dogs"))
print(sentence.replace("Cats", "Dogs"))

Output

I like dogs. Cats are cute.
I like cats. Dogs are cute.

Splitting into words

split() breaks a string into a list of pieces. You'll learn about lists in module 7.

sentence = "Python is really fun"
words = sentence.split()
print(words)
print(len(words), "words")

date = "16-10-2026"
print(date.split("-"))

Output

['Python', 'is', 'really', 'fun']
4 words
['16', '10', '2026']

Searching

email = "asha@example.com"
print("@" in email)
print(email.startswith("asha"))
print(email.endswith(".com"))
print(email.find("@"))
print(email.count("a"))

Output

True
True
True
4
3

Common mistake: Forgetting the brackets: text.upper without () doesn't call the method.