What is the square root of 18?

The square root of 18 is 4.242641. This is not a perfect square. Free instant calculation.

Is 18 a perfect square?

No, 18 is not a perfect square. Its square root is approximately 4.242641.

√18 = 4.242641

Not a perfect square. The result is an irrational number.

The square root of 18 is the number that, when multiplied by itself, equals 18.

18 is not a perfect square, so its square root is an irrational number: approximately 4.242641.

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