Math Calculators
Square Root / Root Calculator
Calculate square, cube and higher roots, including odd roots of negative numbers.
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Square root
9
About the Square Root / Root Calculator
A root reverses exponentiation. The square root of 81 is 9 because 9 squared equals 81, while the cube root of 27 is 3 because 3 cubed equals 27.
Choose a root degree of 2 for square roots, 3 for cube roots or any whole degree of 2 or more for an nth root.
Odd roots of negative numbers are supported as real values. Even roots of negative numbers require complex numbers, so the calculator clearly identifies them as outside its real-number range.
Key features
- Square, cube and higher nth roots
- Odd roots of negative numbers
- Quick degree presets
- Clear real-number validation
How to use
- 1Enter the number whose root you need.
- 2Choose or enter the root degree.
- 3Read the calculated real root.
Frequently asked questions
- What is an nth root?
- The nth root of a number is a value that produces the original number when raised to the power n.
- Can I find the square root of a negative number?
- Not as a real number. Even roots of negative values are complex, while odd roots such as the cube root of -8 are real.
- Is a root the same as a fractional exponent?
- Yes. The nth root of x is equivalent to x raised to the power of 1/n.