How to Create a Class in Python

If you want to group related data and actions together, a class is a good tool to use.

This page shows you how to create your first Python class step by step. You will learn the basic class structure, how to add attributes, how to add methods, and how to create objects from the class.

Quick answer

class Dog:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def bark(self):
        print(self.name, "says woof")

my_dog = Dog("Max", 3)
print(my_dog.name)
my_dog.bark()

Output:

Max
Max says woof

Use class to define the blueprint, __init__ to set starting values, and ClassName(...) to create an object.

What this page helps you do

Create a simple class from scratch
Understand the basic class syntax
Add data to a class with attributes
Add behavior to a class with methods
Create objects from the class

When to use a class

Use a class when:

You want to group related data and actions
Many objects should share the same structure
You are modeling real things like Dog, Car, Student, or BankAccount

Do not use a class for very small one-off values. For example, if you only need a single number or string, a normal variable is enough.

If you are new to this topic, see Python classes and objects explained for a beginner-friendly overview.

Basic syntax for creating a class

To create a class:

Start with the class keyword
Write the class name in PascalCase, such as Person or Car
Add a colon : at the end
Indent everything inside the class

Here is the smallest possible class:

class Person:
    pass

pass means “do nothing for now.” It lets Python accept an empty class.

Add an `init` method

The __init__ method runs when you create a new object.

You usually use it to set starting values for that object.

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

Important parts:

__init__ is a special method
self refers to the current object
name and age are values passed in when the object is created
self.name and self.age store those values in the object

If you want a deeper explanation, read the __init__ method in Python explained.

Create instance attributes

Instance attributes store data for each object.

You create them with self.attribute_name.

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

In this example:

self.name = name stores the person's name
self.age = age stores the person's age

Each object can have different values:

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

person1 = Person("Ana", 25)
person2 = Person("Ben", 31)

print(person1.name)
print(person2.name)

Output:

Ana
Ben

Add methods to the class

Methods are functions inside a class.

Use methods to define what an object can do.

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def introduce(self):
        print("Hi, my name is", self.name, "and I am", self.age, "years old.")

Notice that the method also uses self as the first parameter.

That gives the method access to the object's attributes.

If you want more practice with this part, see how to add methods to a class in Python.

Create an object from the class

You create an object by calling the class name like a function.

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

person1 = Person("Liam", 20)

What happens here:

Person is the class
person1 is an object made from that class
"Liam" goes into name
20 goes into age

Python passes the new object to self automatically.

For more on this step, read how to create an object in Python.

Access attributes and call methods

Use dot notation to work with objects.

Access an attribute

print(person1.name)
print(person1.age)

Call a method

person1.introduce()

Dot notation means:

person1.name gets data from the object
person1.introduce() runs a method on the object

Simple beginner example to include

Here is a complete beginner example using a Person class.

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def introduce(self):
        print("Hi, my name is", self.name, "and I am", self.age, "years old.")

person1 = Person("Sara", 22)

print(person1.name)
print(person1.age)
person1.introduce()

Output:

Sara
22
Hi, my name is Sara and I am 22 years old.

What this code does:

Defines a class named Person
Adds two attributes: name and age
Adds one method: introduce()
Creates one object named person1
Prints the attribute values
Calls the method

Explain class names and style

A few naming rules will make your code easier to read.

Class names usually use PascalCase
- Example: Person, BankAccount, StudentRecord
Method names usually use snake_case
- Example: introduce, get_balance, study_more
Attribute names usually use snake_case
- Example: first_name, account_number

Try to choose names that clearly match the real thing you are modeling.

Good names:

Dog
Car
Student

Less helpful names:

A
X
Thing

If you want the bigger picture, see object-oriented programming in Python explained.

Common mistakes

These are some common beginner mistakes when creating a class.

Forgetting the colon

This causes a syntax error:

class Person
    pass

Correct version:

class Person:
    pass

Not indenting code inside the class

Python requires indentation after the class line.

Wrong:

class Person:
print("hello")

Correct:

class Person:
    print("hello")

If you get this wrong, you may see IndentationError: expected an indented block.

Leaving out `self` in methods

Wrong:

class Person:
    def introduce():
        print("Hello")

Correct:

class Person:
    def introduce(self):
        print("Hello")

Using `name` instead of `self.name`

Wrong:

class Person:
    def __init__(self, name):
        name = name

This does not store the value in the object.

Correct:

class Person:
    def __init__(self, name):
        self.name = name

Trying to access attributes before defining them

Wrong:

class Person:
    def show_name(self):
        print(self.name)

If self.name was never created, Python will fail.

Correct:

class Person:
    def __init__(self, name):
        self.name = name

    def show_name(self):
        print(self.name)

If this happens, you may see AttributeError: object has no attribute.

Misspelling `init`

These are wrong:

__int__
init
_init_

Correct spelling:

def __init__(self, name):
    self.name = name

Debugging tips

If your class is not working, these commands can help you inspect the object.

print(type(my_object))
print(my_object.__dict__)
print(dir(my_object))
help(MyClass)

What they do:

type(my_object) shows the object's class
my_object.__dict__ shows its attributes
dir(my_object) lists available attributes and methods
help(MyClass) shows basic information about the class

FAQ

What is the difference between a class and an object?

A class is the blueprint. An object is one created item based on that blueprint.

You can also read what is a class in Python and what is an object in Python.

Do I always need `init` in a class?

No. But it is the usual way to set starting attribute values.

Why do methods use `self`?

self gives the method access to the current object's attributes and other methods.

Can I create a class with no attributes?

Yes. A class can contain only methods or even be empty at first.

Should beginners learn classes early?

Yes, after functions and basic data types. Start with small real-world examples.