Square Calculator
Calculate x squared (x²) for any integer, negative, or decimal number, with full step-by-step working and the sign rule for negative numbers explained.
What squaring means
Squaring a number means multiplying it by itself:
For example, . The small raised "2" is an exponent — squaring is the same as raising a number to the power of 2.
Why it's called "squaring": the area connection
The name comes from geometry. A square with side length has area — every side is the same length, so the area calculation is literally "the side length, squared." A garden bed that is meters on each side has an area of square meters.
The sign trap: vs.
This is one of the most common mistakes in algebra, because the two expressions look almost identical but mean different things:
| Expression | How to read it | Result |
|---|---|---|
| Negate the result of | ||
| Square the number |
Without parentheses, the exponent applies only to the , and the minus sign is applied after squaring — so . With parentheses, the minus sign is part of the number being squared, so .
This calculator always reads a negative number typed into the field as the whole value being squared. Entering computes , the same way a graphing calculator treats a parenthesized negative base.
Squaring is always non-negative
For any real number :
The smallest possible square is . Every other square — whether is positive or negative — is strictly positive. This is why has no real solution: no real number, positive or negative, squares to a negative value.
Decimal squares, computed exactly
The number being squared doesn't need to be a whole number: . This calculator computes decimal squares with exact decimal arithmetic (not floating-point multiplication), so a value like comes out precise, rather than showing tiny binary-rounding artifacts like .
The inverse: square root
Squaring and taking a square root undo each other. If , then (taking the non-negative root). Because squaring always produces a non-negative result, every positive number has two square roots: and , so both and are square roots of . For the reverse operation — finding from — use the Square Root calculator.
Worked examples
Example 1 — positive integer: .
Example 2 — negative integer: — positive, because the sign cancels.
Example 3 — decimal: .
Example 4 — zero: .
Where squaring shows up
Squaring appears throughout math and science: the area formulas for squares and circles (), the Pythagorean theorem (), variance and standard deviation in statistics, and the inverse-square laws in physics (gravity, light intensity). Squaring is the special case of the Exponents calculator where the exponent is fixed at 2 — cubing (exponent 3) is the next most common special case, with its own dedicated Cube calculator.
Frequently asked questions
- What does squaring a number mean?
- Squaring a number means multiplying it by itself: . For example, . The small "2" is an exponent, so "squared" is another way of saying "raised to the power of 2."
- Is a negative number squared positive or negative?
- Always positive (or zero). Squaring multiplies a number by itself, so two negative signs cancel out: . This calculator reads a negative number typed into the field as the whole value being squared, the same way a graphing calculator treats a parenthesized negative base.
- What is the difference between negative 7 squared and negative-7 in parentheses squared?
- They can mean different things depending on parentheses. (no parentheses) means "negate the result of ," giving . means "square the number ," giving . This calculator treats a negative number typed into the input as the whole base, so entering computes .
- Why is a squared number never negative?
- Because multiplying two numbers with the same sign always gives a positive result. A positive times a positive is positive (), and a negative times a negative is also positive (). So for any real number , — the smallest possible square is .
- Can you square a decimal number?
- Yes. The same rule applies: multiply the decimal by itself. For example, . This calculator computes decimal squares exactly, using exact decimal arithmetic rather than floating-point multiplication, so results like come out precise instead of showing tiny rounding artifacts.
- What is the inverse of squaring?
- The inverse of squaring is taking the square root. If , then (for non-negative ). Since squaring always gives a non-negative result, every positive number has two square roots — a positive and a negative one — because both and square to the same value .
- How is squaring used to calculate area?
- The area of a square with side length is , because a square has equal width and height, so area = width × height = . This is where the name "squaring" comes from: multiplying a number by itself is exactly the calculation you do to find the area of a square.