Square Root Calculator
Calculate square roots and other whole-number roots.
Square root
9
- Check
- 9 ^ 2 = 81
What this calculator does
Find square, cube, and higher roots with real-number validation for negative values.
Inputs and what they mean
- Number
- — number value.
- Root index
- — number value.
How to use it
- Enter the requested values.
- Choose the calculation mode when available.
- Review the result and supporting breakdown.
Formula
The nth root of x is x^(1/n). Negative numbers have real roots only for odd integer indices.
Worked example
Square root of 81
√81 = 9.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
Results depend entirely on the figures you enter and are rounded for display. They are for general information and education, not professional advice.
Common questions
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