This square root calculator instantly computes the square root of any positive number. Enter a value and the result updates in real time, with a badge showing when you've found a perfect square.
Square root calculator
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What is a square root?
The square root of a number is the value that, when multiplied by itself, equals the original number. Written as √x or x^(1/2).
For example: √16 = 4, because 4 × 4 = 16.
Square roots only exist for non-negative numbers in the real number system. The square root of a negative number is undefined without imaginary numbers. Square root is the inverse of squaring a number.
Perfect squares
A perfect square is a number whose square root is a whole number. The calculator displays a "Perfect Root" badge when you enter one. The first few perfect squares:
- 1 (1²)
- 4 (2²)
- 9 (3²)
- 16 (4²)
- 25 (5²)
- 36 (6²)
- 49 (7²)
- 64 (8²)
- 81 (9²)
- 100 (10²)
