Python Assignment Operators

Summary: in this tutorial, you’ll learn how to use the Python assignment operators to assign values to variables.

Assignment operator #

In Python, you use the assignment operator to assign a value to a variable. For example, the following use the assignment operator (=) to assign number 0 to the variable count:

count = 0

print(count)Copy

Try it

Output:

0Copy

You can perform a calculation on a variable and assign the result back to it as follows:

count = 0
count = count + 1

print(count)Copy

Try it

Output:

1Copy

In this example, we assign 0 to the count variable and then increment its value by one and assign it back to the count variable.

Note that the = in the following expression is an assignment, not equal comparison:

count = count + 1Copy

In Python, the equal operator that compares two values is ==. You’ll learn it in the comparison operators tutorial.

Compound Assignment Operators #

In programming, we often want to express our ideas concisely. For example, you can increment the count variable and assign its result back to the variable in one step using the compound assign operator +=:

count = 0
count += 1

print(count)Copy

Try it

Output:

1Copy

In this example, the operator += adds one to the count variable and assigns its result back to the variable:

count += 1Copy

It’s equivalent to the following:

count = count + 1Copy

Here are the common compound assignment operators in Python:

Add and Assign (+=) #

The add and assign operator (+= ) allows you to add a value to a variable and assign the result back to it. For example:

count = 0
count += 1  # Same as: count = count + 1

print(count)Copy

Try it

Output:

1Copy

Subtract and Assign (-=) #

The subtract and assign operator (-=) allows you to subtract a value from a variable and assigns the result back to the variable:

quantity = 5
quantity -= 2  # Same as: quantity = quantity- 2

print(quantity)Copy

Try it

Output:

3Copy

Multiply and Assign (*=) #

The multiply and assign operator ( *= ) operator allows you to multiply a number and assigns the result back to the variable:

a = 10
a *= 2  # Same as: a = a * 2

print(a)  # Output: 20Copy

Try it

Output:

20Copy

Divide and Assign (/=) #

The divide and assign operator ( /= ) allows you to divide and assign the result:

amount = 25
amount /= 2 # same as amount = amount / 2

print(amount)Copy

Try it

Output:

12.5Copy

Floor Divide and Assign (//=) #

The floor divide and assign operator ( //= ) allows you to perform integer division and assign a value back:

amount = 10
amount //= 3  # Same as: amount = amount // 3

print(amount)Copy

Try it

Output:

3Copy

Modulus and Assign (%=) #

The modulus and assign operator ( %=) calculates the remainder and assigns it to a variable:

amount = 10
amount %= 3

print(amount)Copy

Try it

Output:

1Copy

Exponentiate and Assign (**=) #

The exponentiate and assign operator (**= ) allows you to raise a number to a power and assign the result back:

a = 2
a **= 3  # Same as: a = a ** 3
print(a)Copy

Try it

Output:

8Copy

Summary #

• Use the assignment operator (=) to assign a value to a variable.
• Use compound assignment operators to calculate and assign the result to a variable in one step.

Quiz #