fstrings in Python (original) (raw)

f-strings in Python

Last Updated : 16 May, 2026

f-strings (formatted string literals) were introduced in Python 3.6 to make string formatting easier and more readable. They allow variables and expressions to be directly embedded inside strings using curly braces {}.

Python `

name = "Emily" age = 20 print(f"My name is {name} and I am {age} years old")

`

Output

My name is Emily and I am 20 years old

Syntax

An f-string is created by adding f before the string and placing variables or expressions inside {}.

f"{variable/expression}"

Examples

**Example 1: This example formats and prints the current date using an f-string.

Python `

import datetime today = datetime.datetime.today() print(f"{today:%B %d, %Y}")

`

**Explanation:

• datetime.datetime.today() gets the current date.
• %B, %d and %Y format the month, day and year.
• f-string inserts the formatted date into the string.

**Note: F-strings are faster than the two most commonly used string formatting mechanisms, which are % formatting and str.format().

**Example 2: This example shows how single, double and triple quotes can be used in f-strings.

Python `

print(f"'GeeksforGeeks'") print(f"""Geeks"for"Geeks""") print(f'''Geeks'for'Geeks''')

`

Output

'GeeksforGeeks' Geeks"for"Geeks Geeks'for'Geeks

**Explanation:

• f-strings support single, double and triple quotes. Different quote styles help avoid syntax errors.
• Triple quotes allow quotes to be used easily inside strings.

**Example 3: This example evaluates an expression directly inside an f-string.

Python `

Physics = 78 Chemistry = 56 Biology = 85 print(f"Alex got total marks {Physics + Chemistry + Biology} out of 300")

`

Output

Alex got total marks 219 out of 300

Errors while Using f-strings

**1. Missing Closing Braces: Every opening curly brace { in an f-string must have a matching closing brace }.

Python `

name = "Jake" print(f"My name is {name")

`

**Output

ERROR!
Traceback (most recent call last):
File "<main.py>", line 2
print(f"My name is {name")
^
SyntaxError: f-string: expecting '}'

**2. Using Undefined Variables: Variables used inside an f-string must be defined before they are used.

Python `

print(f"My age is {age}")

`

**Output

ERROR!
Traceback (most recent call last):
File "<main.py>", line 1, in
NameError: name 'age' is not defined