Square Root of 81
√81 = 9
Perfect Square ✓
How to Find the Square Root of 81
The square root of 81 is the number that, when multiplied by itself, equals 81.
Since 9 × 9 = 81, the square root is exactly 9. This makes 81 a perfect square.
Nearby Square Roots
| Expression | Result |
|---|---|
| √76 | 8.717798 |
| √77 | 8.774964 |
| √78 | 8.831761 |
| √79 | 8.888194 |
| √80 | 8.944272 |
| √81 | 9 |
| √82 | 9.055385 |
| √83 | 9.110434 |
| √84 | 9.165151 |
| √85 | 9.219544 |
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