Toolical © 2026

Square Root Calculator

Compute the square root of any non-negative number.

Result
Please check your inputs.
Enter any non-negative number into the input field labeled 'Number'. Click the 'Calculate Square Root' button. Instantly view the principal square root result displayed below. Use the 'Clear' button to reset the input and perform a new calculation. For decimal precision, the result shows up to 10 decimal places.

📖 How to Use This Tool

Enter any non-negative number into the input field labeled 'Number'.
Click the 'Calculate Square Root' button.
Instantly view the principal square root result displayed below.
Use the 'Clear' button to reset the input and perform a new calculation.
For decimal precision, the result shows up to 10 decimal places.

📝 What Is Square Root Calculator?

The square root of a number is a value that, when multiplied by itself, gives the original number. For instance, the square root of 9 is 3 because 3 × 3 = 9. This tool computes the principal (non-negative) square root for any non-negative input, including zero and decimal numbers. Square roots are fundamental in mathematics, science, and engineering — they appear in geometry (finding side lengths of squares), physics (calculating velocity), finance (risk assessment), and daily life (estimating quantities). Understanding square roots helps simplify complex equations and make sense of growth rates, areas, and standard deviations. Our calculator removes manual computation errors, letting you focus on interpretation and application.

🧮 Formula

The tool uses the formula √x = y, where y ≥ 0 and y² = x. In plain English: the square root of x (written as √x) is the non-negative number y that, when squared (multiplied by itself), equals x. For example, √16 = 4 because 4 × 4 = 16. For most numbers, the result is irrational (non-terminating decimal), so the calculator rounds to a high precision.

💡 Tips for Best Results

🧮 Start with perfect squares (1, 4, 9, 16, 25) to verify the tool behaves as expected.
📐 Use the square root to find side lengths of squares when you know the area — just input the area.
🔢 If you need the negative square root, simply add a minus sign before the result.
⚡ For quick mental checks: the square root of a number is always less than or equal to the number (except for numbers between 0 and 1).

Frequently Asked Questions

Can I enter negative numbers?
No, this calculator only accepts non-negative numbers because the square root of a negative number is not a real number (it's an imaginary number). If you need imaginary results, consider a complex number calculator.
How accurate is the result?
The result is accurate to 10 decimal places, which is sufficient for nearly all academic, professional, and everyday purposes. For perfect squares, the result will be exact.
What is the square root of 0?
The square root of 0 is 0, because 0 × 0 = 0. This is consistent with the definition and our calculator will correctly return 0.

🔗 Related Tools