√4 = 2. The square root of 4 is 2, because 2 × 2 = 4. 4 is a perfect square.
√4 at a glance.
Value
2
Rounded
2
Perfect square?
Yes
4 squared
16
Checking it in your head
A perfect square's root is a whole number, so check by multiplying back: 2 × 2 = 4. Its last digit fits too: squares only ever end in 0, 1, 4, 5, 6 or 9, and 2² ends in 4.
Frequently asked questions
What is the square root of 4?
The square root of 4 is 2, because 2 × 2 = 4. 4 is a perfect square.