String formatting in Python allows you to create dynamic, readable, and structured text by inserting variables into strings. It’s a powerful tool for displaying messages, logging, and generating user-friendly outputs.

In this tutorial, you’ll learn the most common and effective string formatting methods:

• format() method
• f-strings (formatted string literals)
• % formatting (legacy)

Why Format Strings?

Instead of this:

name = "Alice"
age = 25
print("My name is " + name + " and I am " + str(age) + " years old.")

Use formatting:

print(f"My name is {name} and I am {age} years old.")

Much cleaner and more readable!

Method 1: format() Method

This method uses curly braces {} as placeholders and .format() to fill them.

Basic Example:

name = "Alice"
print("Hello, {}".format(name))  # Output: Hello, Alice

 Multiple Variables:

name = "Bob"
age = 30
print("Name: {}, Age: {}".format(name, age))

 Positional Indexing:

print("I like {1} more than {0}".format("Java", "Python"))
# Output: I like Python more than Java

Named Placeholders:

print("My name is {first} {last}".format(first="John", last="Doe"))

Method 2: f-Strings (Python 3.6+)

f-strings (formatted string literals) are the most modern and preferred method for string formatting.

 Basic Example:

name = "Eve"
age = 28
print(f"My name is {name} and I am {age} years old.")

Expressions Inside f-Strings:

price = 49.99
quantity = 3
print(f"Total: ${price * quantity:.2f}")
# Output: Total: $149.97

✅ Cleaner, faster, and supports inline expressions.

 Method 3: % Operator (Old Style)

This is the legacy way of formatting strings (similar to C-style formatting).

Basic Example:

name = "Alice"
print("Hello, %s" % name)

With Multiple Variables:

name = "Bob"
age = 25
print("Name: %s, Age: %d" % (name, age))

Format Code

⚠️ Use this method only if you're maintaining older Python code.

 Formatting Numbers

Decimal Precision:

pi = 3.14159
print(f"Value of Pi: {pi:.2f}")  # Output: 3.14

Padding and Alignment:

text = "Hi"
print(f"{text:>10}")  # Right-align in 10 spaces

Summary Table