To find the complement of an angle, the formula is:

$\text{Complement of an angle} = 90^\circ - \text{given angle}$

In this case, the given angle is $45^\circ$. So,

$\text{Complement of } 45^\circ = 90^\circ - 45^\circ = 45^\circ$

Thus, the complement of $45^\circ$ is $45^\circ$.

Would you like further details or have any additional questions?

Here are 5 related questions to consider:

1. What is the complement of a $30^\circ$ angle?
2. How is the concept of complementary angles used in trigonometry?
3. What is the difference between complementary and supplementary angles?
4. What happens when an angle is more than $90^\circ$ — can it have a complement?
5. How do complementary angles relate to right triangles?

Tip: Remember, complementary angles always add up to $90^\circ$.