How to Iterate Over String in Python: Simple Guide

To iterate over a string in Python, use a for loop to access each character one by one. The syntax is for char in string: where char represents each character during the loop.

Syntax

The basic syntax to iterate over a string uses a for loop. You write for char in string: where string is your text and char is each character you get one at a time.

Inside the loop, you can use char to work with each character.

python

for char in string:
    # do something with char

Example

This example shows how to print each character of a string on its own line using a for loop.

python

my_string = "hello"
for char in my_string:
    print(char)

Output

h
e
l
l
o

Common Pitfalls

One common mistake is trying to use a for loop without specifying the string variable, or trying to access characters by index without a loop.

Another is modifying the string inside the loop, which is not allowed because strings are immutable in Python.

python

wrong_string = "hello"
# Wrong: trying to change characters directly
for char in wrong_string:
    char = char.upper()  # This does not change the original string

# Right way: build a new string
new_string = ""
for char in wrong_string:
    new_string += char.upper()
print(new_string)

Output

HELLO

Quick Reference

Remember these tips when iterating over strings:

• Use for char in string: to get each character.
• Strings cannot be changed directly; create a new string if needed.
• You can use enumerate(string) to get both index and character.

Key Takeaways

Use a for loop with for char in string: to iterate over each character.

Strings are immutable; you cannot change characters directly inside the loop.

Build a new string if you want to modify characters during iteration.

Use enumerate(string) to get both index and character if needed.