Calculadora de Raiz Quadrada

Raiz quadrada principal (positiva) de um número real não-negativo.
Created by
Renato Passos, Eng. de Software
Reviewed by
Renato Passos, Eng. de Software

Last updated: Apr 18, 2026

√n
12,000000

Formula

r = √n

About this calculator

The Square Root Calculator is an online tool that computes the principal (positive) square root of a non-negative real number. The square root of a number n is the value r such that r² = n. For example, the square root of 9 is 3, because 3² = 9. This calculator is useful for students, teachers, and professionals who need quick and accurate results.

Operation is simple: you enter a non-negative number in the field and click calculate. The system applies the mathematical function sqrt(n) to obtain the result. The calculator handles decimal and integer numbers and returns the square root with up to 10 decimal places. It is ideal for checking manual calculations or solving everyday problems.

Use this calculator in situations such as checking math exercises, calculating dimensions of square areas (e.g., the side of a square from its area), or in engineering and finance applications involving square roots. Remember that only non-negative numbers have real square roots. For negative numbers, the result is not a real number.

Cautions: ensure the entered number is non-negative. The square root of zero is zero. For very large numbers, the result may be approximate due to numerical precision limitations. Always verify the result with a physical calculator or reliable software in critical cases.

Frequently asked questions

What is a square root?

The square root of a number n is the value r that, when multiplied by itself, gives n. For example, the square root of 16 is 4, because 4 x 4 = 16.

Can I calculate the square root of a negative number?

No, negative numbers do not have real square roots. The result would be an imaginary number, which is not supported by this calculator.

How to calculate square root without a calculator?

You can use methods like successive approximations or Newton's method. For small numbers, memorizing perfect squares helps.

Is the square root of zero zero?

Yes, the square root of zero is zero, because 0 x 0 = 0.

What is the difference between principal and non-principal square root?

The principal square root is the non-negative value. Every positive number has two square roots: one positive and one negative. This calculator returns only the positive one.

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