Calcubes

Square Root Calculator

Calculate the square root of any non-negative number. The square root of x is the number that when multiplied by itself equals x. Free online square root calculator for math, geometry, and everyday calculations.

Square root calculator

Square root

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What is this?

The square root of a number x is the value that, when multiplied by itself, gives x. Written as √x. For example, √144 = 12 because 12 × 12 = 144. Only defined for non-negative numbers in real numbers. The square root is the inverse of squaring: if you square 8 you get 64, so the square root of 64 is 8. The calculator handles decimals and large numbers. It returns the principal (non-negative) square root. For negative numbers, you would need complex numbers, which this calculator does not support.

When to use

Use for geometry (side length of a square from area), Pythagorean theorem, standard deviation, or any math involving roots. Example: Area 64 m² → side = √64 = 8 m. Geometry students find side lengths from area. The Pythagorean theorem (a² + b² = c²) often requires taking square roots to find c. Standard deviation formulas use square roots. Engineers and scientists use it in various calculations. Quick and accurate for any non-negative input.

How to use

Enter a non-negative number. √x is the number that when multiplied by itself gives x.

Frequently asked questions

What is a square root?
The square root of a number x is the number that when multiplied by itself equals x. For example, √144 = 12 because 12 × 12 = 144.
Can I calculate the square root of negative numbers?
No. The square root of a negative number is not a real number. This calculator only accepts non-negative inputs.

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