Square Root Calculator
Enter a number and instantly get its square root with high precision.
Enter a non-negative number to take the square root
About the square root calculator
The square root of a number is the value that, when multiplied by itself, gives that number. For example, the square root of 25 is 5 because 5 × 5 = 25.
This calculator not only finds the root but also tells you whether your number is a perfect square (like 16, 25, or 36) or whether its root is an irrational number with an endless, non-repeating decimal.
All calculations run instantly right in your browser — your number is never uploaded or stored, keeping the computation completely local and private.
Benefits
High precision
The square root is computed to many decimal places, which is handy for homework and exact work.
Perfect square detection
The calculator instantly tells you whether the number is a perfect square or has an irrational root.
Instant and private
Results appear as you type, and your data never leaves your browser.
Frequently asked questions
How do I find the square root of a number?
Find the value that, multiplied by itself, gives your number. Just type the value into the field and the calculator works out the root automatically.
What is a perfect square?
A perfect square is a number whose square root is a whole number. For example, 49 is a perfect square because its square root is 7.
Why is a square root sometimes irrational?
If a number isn't a perfect square, its root can't be written as a finite decimal — it's an irrational number, such as the square root of 2 ≈ 1.41421356.
Can I take the square root of a negative number?
Not within the real numbers — a negative number has no real square root, so the calculator will show a warning instead.
Are my numbers saved?
No. Every calculation happens locally in your browser, so your number is never sent to a server or stored.