← GradeWeight Home

Square Root Calculator

Find the square root of any number — the simplified radical form with steps, plus the decimal value. Free in your browser.

Calculate a square root



How to simplify a square root

Find the largest perfect square that divides the number, then take its root outside the radical. Example: √72 — the largest perfect square dividing 72 is 36, so √72 = √(36 × 2) = 6√2 (about 8.4853).

Worked examples

Example 1 — √50. The largest perfect square dividing 50 is 25. √50 = √(25 × 2) = 5√2 (about 7.0711).

Example 2 — √48. The largest perfect square dividing 48 is 16. √48 = √(16 × 3) = 4√3 (about 6.9282).

Example 3 — √98. The largest perfect square dividing 98 is 49. √98 = √(49 × 2) = 7√2 (about 9.8995).

Example 4 — √75. The largest perfect square dividing 75 is 25. √75 = √(25 × 3) = 5√3 (about 8.6603).

Perfect squares worth remembering

1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144. If your number is one of these, its square root is a whole number: √144 = 12.

Frequently Asked Questions

What is a square root? The square root of a number is the value that, multiplied by itself, gives the number. For example, the square root of 25 is 5, because 5 × 5 = 25.

What does it mean to simplify a square root? Pulling out the largest perfect square factor. For example, √72 = √(36 × 2) = 6√2, because 36 is the largest perfect square dividing 72.

What is the square root of a negative number? Real square roots of negative numbers do not exist. This calculator works with zero and positive numbers only.

What is the difference between √ and ∛? √ is the square root (the number times itself gives the original). ∛ is the cube root (the number times itself twice). This page handles square roots only.

Why does my answer show a decimal and a radical? Most square roots are irrational — they never end. The radical form (like 6√2) is exact; the decimal (like 8.4853) is rounded for everyday use. Teachers usually want the radical form.

How do I estimate a square root by hand? Find the two perfect squares your number sits between. For √50: 49 < 50 < 64, so the answer is just above 7 — the calculator gives 7.0711.

Is this calculator free? Yes. It runs in your browser; nothing is uploaded.

More calculators

Weighted Grade Calculator · Simplify Calculator · Factor Calculator · Final Exam Calculator · Molarity Calculator

Educational tool only. For schoolwork, always check your teacher's required format.