Square Root Calculator — √ Find Square Root of Any Number

What is a Square Root?

This free square root calculator — also called a sqrt calculator or square root finder — instantly finds the square root, cube root, and 4th root of any number to 6 decimal places. Use it to find square root online without a scientific calculator. The square root of a number n is the value x such that x² = n. For example, the square root of 144 = 12 (because 12² = 144), the square root of 2 = 1.41421, and the square root of 3 = 1.73205. This cube root calculator also handles ∛n: ∛8 = 2, ∛27 = 3, ∛125 = 5, ∛1000 = 10. Enter any number into the square root finder to get all roots at once. Square roots appear throughout geometry (Pythagorean theorem: hypotenuse = √(a²+b²)), physics (velocity, energy), statistics (standard deviation = √variance), and finance (volatility scales with √T). The Common Square Roots Reference Table below covers √1 through √10,000 for instant lookup.

How to Use This Calculator

Enter any non-negative number in the input field and click Calculate. The sqrt calculator instantly shows the square root (√n), cube root (∛n), and 4th root (∜n) all to 6 decimal places, along with n² and n³ for complete reference. For negative numbers, the calculator correctly identifies the result as an imaginary number. Works for decimals, large numbers, and perfect squares alike. To find square root online of a specific value, just type it in — no sign-up required.

💡 Pro Tips

• ✓Perfect squares have whole-number square roots: √4=2, √9=3, √16=4, √25=5, √36=6, √49=7, √64=8, √81=9, √100=10, √121=11, √144=12. See the full reference table on this page.
• ✓For the Pythagorean theorem, enter (a² + b²) into this square root calculator to get the hypotenuse — e.g., a 3-4-5 triangle: √(9+16) = √25 = 5.
• ✓Standard deviation in statistics equals √variance — use this sqrt calculator by entering your variance value directly.
• ✓The square root of 2 (√2 = 1.41421) appears in diagonal measurements — a 1×1 square has a diagonal of exactly √2 units.
• ✓Asset volatility over T days = daily volatility × √T — a key formula in finance that uses this square root finder.
• ✓Cube roots are the inverse of cubing: the cube root calculator gives ∛125 = 5 because 5³ = 125; ∛1000 = 10 because 10³ = 1000.

Who Uses This Calculator?

Students checking homework — search "square root of 144", "square root of 2", or "sqrt of any number" and verify here instantly. Anyone who needs to find square root online without a calculator app. Geometry students applying the Pythagorean theorem. Physics and engineering students computing RMS values, standard deviations, and signal amplitudes. Financial analysts using the √T volatility rule. Teachers and tutors looking up common square roots for class. Anyone needing a quick cube root calculator for ∛n values.

Frequently Asked Questions

Perfect squares highlighted · values rounded to 3 decimal places