Square Root of 400
√400 = 20
Perfect Square ✓
How to Find the Square Root of 400
The square root of 400 is the number that, when multiplied by itself, equals 400.
Since 20 × 20 = 400, the square root is exactly 20. This makes 400 a perfect square.
Nearby Square Roots
| Expression | Result |
|---|---|
| √395 | 19.874607 |
| √396 | 19.899749 |
| √397 | 19.924859 |
| √398 | 19.949937 |
| √399 | 19.974984 |
| √400 | 20 |
| √401 | 20.024984 |
| √402 | 20.049938 |
| √403 | 20.074860 |
| √404 | 20.099751 |
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