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How to Use Square Root Calculator

Calculate the square root of any number to up to 50 decimal places, check if it is a perfect square and see the simplified radical form. Free calculator.

About this tool

The square root calculator finds √x to high precision, up to 50 decimal places, using exact integer arithmetic. It tells you whether the number is a perfect square, shows the simplified radical form for whole numbers (so √72 becomes 6√2) and handles negative numbers by showing the imaginary result.

How to use Square Root Calculator

  1. Enter a number, whole or decimal.
  2. Choose how many decimal places you need.
  3. Read the square root, the perfect-square check and the simplified radical form.

Worked example

√72 ≈ 8.4852813742. 72 is not a perfect square, but it simplifies to 6√2 because 72 = 36 × 2 and √36 = 6.

What is a square root?

The square root of x is the number that, multiplied by itself, gives x. √49 = 7 because 7 × 7 = 49.

How do I simplify a square root?

Find the largest perfect square that divides the number, take its root outside and leave the rest inside: √72 = √(36 × 2) = 6√2.

What is the square root of a negative number?

There is no real answer. In complex numbers, √−9 = 3i, where i is the square root of −1.

Put this guide into practice

  • Square Root Calculator — Find the square root of any number to high precision, with simplified radical form.

Explore Math Calculators · More practical guides

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