√16 = 4. The square root of 16 is 4, because 4 × 4 = 16. 16 is a perfect square.
√16 at a glance.
Value
4
Rounded
4
Perfect square?
Yes
16 squared
256
Checking it in your head
A perfect square's root is a whole number, so check by multiplying back: 4 × 4 = 16. Its last digit fits too: squares only ever end in 0, 1, 4, 5, 6 or 9, and 4² ends in 6.
Frequently asked questions
What is the square root of 16?
The square root of 16 is 4, because 4 × 4 = 16. 16 is a perfect square.