Square roots·√15
√15 =
√15
≈ 3.872983

Square root of 15 — 3.872983 (√15)

Irrational

The square root of 15 is about 3.872983, or exactly √15. It lies between 3 and 4.

As a decimal
≈ 3.872983
Simplified surd
√15 = √15
Between
3 < √15 < 4
Squared
15² = 225
Cube root
∛15 ≈ 2.466212

Nearby numbers

√12 = 2√3√13 = √13√14 = √14√16 = 4√17 = √17√18 = 3√2

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 15?

About 3.872983, or exactly √15.

Q. Can the surd be simplified?

No — there is no square factor to pull out.

Q. Between which integers does it fall?

Between 3 and 4.

Q. What is the cube root of 15?

About 2.466212.