Find any square root. This free square root calculator gives the decimal value and the simplified radical form (like √72 = 6√2), tells you if it’s a perfect square, and handles cube and nth roots too.
Find a root
Enter a number to find its square root (or cube/nth root). For square roots, the calculator also gives the simplified radical form, like √72 = 6√2.
Square root
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Enter a number
Simplified radical
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Perfect square?
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Square (n²)
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Cube (n³)
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The square root of a number is the value that, multiplied by itself, gives that number. Negative numbers have no real square root (the calculator notes this).
Use this free square root calculator to find the square root of any number. It also gives the simplified radical form (like √72 = 6√2), and can find cube roots and nth roots.
What this square root calculator does
A square root calculator finds the value that, multiplied by itself, gives your number. This one shows the decimal result, the simplified radical form, whether the number is a perfect square, and can also compute cube roots and nth roots.
How square roots work
√x = y means y × y = x
Example: √64 = 8, because 8 × 8 = 64
When a number isn’t a perfect square, it can often be simplified by pulling out perfect-square factors — for example, √72 = √(36 × 2) = 6√2.
Perfect squares
n
n²
√(n²)
4
16
4
9
81
9
12
144
12
25
625
25
Can you take the square root of a negative number?
Not within the real numbers — no real value squared gives a negative result. (In mathematics these are handled with imaginary numbers, e.g. √−1 = i.) For odd roots like cube roots, a negative input is fine: ∛−8 = −2.
How to use the square root calculator
Enter your number.
Choose square, cube or nth root.
Read the result and, for square roots, the simplified radical.
Square Root FAQ
How do I find a square root?
Enter your number and the calculator returns its square root — the value that multiplied by itself gives your number. √64 is 8, because 8 × 8 = 64.
How do I simplify a square root?
Pull out the largest perfect-square factor. For √72, that's 36, so √72 = √(36 × 2) = 6√2. The calculator shows this simplified radical form automatically.
What is a perfect square?
A number whose square root is a whole number, like 16 (4²) or 144 (12²). The calculator tells you whether your number is a perfect square.
Can you take the square root of a negative number?
Not in the real numbers — no real value squared is negative. (Mathematically it's handled with imaginary numbers.) Odd roots like cube roots do work on negatives, so ∛−8 = −2.
Can it find cube roots and other roots?
Yes. Switch to cube root, or choose "nth root" and enter n to find any root, such as the 4th root of 16, which is 2.
Is the square root calculator free?
Yes, this square root calculator is completely free, needs no sign-up, and gives instant results in your browser.
