Square Root of 961

The square root of 961 is exactly 31, because 31 × 31 = 961. The negative number −31 squares to 961 too.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Decimal
31
Both real square roots
±31x² = 961 has two real solutions
Perfect power?
Yes
√96131

Show the work

  1. 961 is a perfect square: 312 = 961.
  2. So √961 = 31.

√961 at a glance

Exact value
31
Decimal (10 places)
31
Rounded
31
Perfect square?
Yes — 31²
Rational?
Rational (whole number)
Both square roots
±31
Prime factorization
31²
Cube root
9.868272

How to simplify √961

Write 961 as a product of primes and halve every exponent. Because each exponent is even, nothing is left under the radical sign:

961 = 31²
√961 = 31 = 31

961 has 2 factor pairs (1 × 961, 31 × 31). The pair with two equal numbers, 31 × 31, is what makes it a perfect square — and why it has an odd number of factors.

Every perfect square is also a sum of consecutive odd numbers starting at 1. Here 961 = 1 + 3 + 5 + 7 + … + 61, the first 31 odd numbers.

Where √961 sits between perfect squares

961 is 31². The perfect squares on either side are 900 (30²) and 1,024 (32²), so the gaps are 61 below and 63 above — consecutive squares always differ by consecutive odd numbers.

3030² = 9003131² = 9613232² = 1,024√961 = 31
√961 on a number line, with tenths marked between 30 and 32.

Finding √961 with the Babylonian method

This is Newton’s method applied to f(x) = x² − 961: following the tangent line down to zero simplifies to averaging x with 961 ÷ x.

xnext = (x + 961 ÷ x) ÷ 2

To show the method at work on a perfect square, start one above the answer, at 32:

StepGuess x961 ÷ xAverageCorrect decimals
132.000000000030.031250000031.01562500001
231.015625000030.984382871531.00000393585
331.000003935830.999996064231.0000000000all 10 shown

The count of correct decimals went 1, 5 and all 10 over 3 steps — roughly doubling each time — until the guess matched √961 = 31.0000000000 to every decimal shown.

√961 in geometry and everyday measurements

  • 961 square feet is 89.3 m². Laid out as a square — a small house footprint or a lot — it is exactly 31 ft (31 ft) on a side.
  • 961 is not a sum of two whole-number squares — no pair of squares adds up to it — so √961 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 5 × 6 × 30 box, because 5² + 6² + 30² = 961.
RootSimplest formDecimalPerfect square?
√958√95830.9516No
√959√95930.9677No
√9608√1530.9839No
√9613131.0000Yes
√962√96231.0161No
√9633√10731.0322No
√9642√24131.0483No
  • The cube root of 961 is about 9.868272.
  • Taking the square root twice gives the fourth root: √31 ≈ 5.567764.
  • Squaring undoes the root: (√961)² = 961, while 961² = 923,521 — the number whose square root is 961.

Frequently asked questions

What is the square root of 961?

The square root of 961 is 31, because 31 × 31 = 961. Strictly, 961 has two square roots, 31 and −31; the √ symbol means the positive one.

Is the square root of 961 rational or irrational?

Rational. 961 is a perfect square, so its square root is the whole number 31.

Can √961 be simplified?

Yes, all the way to a whole number: √961 = 31.

What is √961 rounded to two decimal places?

√961 is exactly 31, or 31.00 written to two decimal places.

Need a different value? Use the Square root calculator, or browse the Square roots 1–1,000.