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

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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