√4 =
2
Exact
Square root of 4 — 2
Exact
The square root of 4 is 2, because 2 × 2 = 4.
- As a decimal
- 2
- Simplified surd
- √4 = 2
- Between
- 2
- Squared
- 4² = 16
- Cube root
- ∛4 ≈ 1.587401
How the surd is simplified
Pull out the largest square factor. Since 50 = 25 × 2, the root of 25 comes out as 5 and the 2 stays behind: 5√2.
√4 = √(4 × 1) = 2
Nearby numbers
From 1 to 200
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How to read this
- The decimal is rounded; the surd form is the exact value.
- Pulling out a square factor simplifies the surd — √50 = 5√2.
- If the number is not a perfect square, the decimal never ends (irrational).
- Knowing which two integers it sits between is enough to estimate in your head.
Frequently asked questions
Q. What is the square root of 4?
2 exactly.
Q. Can the surd be simplified?
Yes: 4 = 4 × 1, so 2 comes out and it becomes 2.
Q. Between which integers does it fall?
It is the whole number 2.
Q. What is the cube root of 4?
About 1.587401.