Math
Square Root Calculator
Use this square root calculator to find decimal square roots and simplified radical form when the input is a nonnegative whole number.
Try an example
Result
Square root
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- Decimal
- —
Student quick launch
Grade planning, algebra checks, and formulas students reach for most.
Study path
Use this calculator with
Follow these when you want the formula behind the answer, a short lesson, or nearby tools in the same topic.
What the square root calculator solves
Use this square root calculator to find decimal square roots and simplified A root expression written with the √ symbol, such as a square root. form when the input is a nonnegative whole number.
Formula
How to use it
- Enter a nonnegative number.
- Read the simplified radical when available.
- Use the decimal approximation when you need a numeric value.
How to read the answer
The principal square root is nonnegative. Negative square roots require complex numbers and are not shown in this basic calculator.
Common mistakes and edge cases
- sqrt(a+b) is not sqrt(a)+sqrt(b).
- Do not forget that squaring a negative also gives a positive.
- Only nonnegative real inputs have real square roots.
Worked examples
Simplify radical
Square root
6sqrt(2) = 8.48528137
Perfect square
Square root
12 = 12
Frequently asked questions
Why is the square root of 72 equal to 6sqrt(2)?+
Because 72 = 36 x 2, and sqrt(36) comes out of the radical as 6.
Does this show negative square roots?+
It shows the principal square root. Equations like x^2 = 9 have both +3 and -3 as solutions.
About this calculator
- Written by
- mathcheck editorial team
- Last reviewed
- May 8, 2026
Method
- Uses the values entered by the user and stable formulas documented on the page.
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Last updated: May 8, 2026