Square Root of 160

The square root of 160 is 4√10 in simplest radical form, or about 12.6491106407 as a decimal.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
4√10
Decimal
12.6491106407
Both real square roots
±12.6491106407x² = 160 has two real solutions
Between
12² = 144 and 13² = 169so the root is between 12 and 13
Perfect power?
No
√16012.6491106407= 4√10

Show the work

  1. Prime-factor the radicand: 160 = 25 × 5 = (24) × 2 × 5.
  2. Each pair of identical factors comes out of the radical as a single factor: √160 = 4√10.
  3. Decimal value: √160 ≈ 12.6491106407.
  4. Check: 12.64911064072 ≈ 160.

√160 at a glance

Exact value
4√10
Decimal (10 places)
12.6491106407
Rounded
12.6 · 12.65 · 12.649
Perfect square?
No — between 12² and 13²
Rational?
Irrational
Both square roots
±12.649111
Prime factorization
2⁵ × 5
Cube root
5.428835

How to simplify √160

Look for the largest perfect square that divides 160. Here it is 16 (4²), because 160 = 16 × 10 and 10 has no square factor left:

√160 = √(16 × 10) = √16 × √10 = 4√10

The prime factorization tells the same story: 160 = 2⁵ × 5. Each pair of equal primes leaves the radical as one factor, so 2² comes out and 2 × 5 stays inside.

160 has 2 square factors (4 and 16). Starting with a smaller one still works but takes more rounds: √160 = 2√40, and √40 can be simplified again. Using 16 straight away finishes in one step.

Check: (4√10)² = 4² × 10 = 16 × 10 = 160. As a decimal, 4√10 = 4 × 3.1622776602 ≈ 12.6491106407.

Where √160 sits between perfect squares

144 = 12² and 169 = 13² are the nearest perfect squares, so √160 lies between 12 and 13. 160 is 16 above 144 and 9 below 169, so the root is closer to 13.

√160 ≈ 12 + (160 − 144) ÷ (169 − 144) = 12 + 16/25 ≈ 12.6400
  • Straight line between 144 and 169: 12.6400 (0.07% low)
  • Tangent from 12, i.e. 12 + 16 ÷ 24: 12.6667 (0.14% high)
  • Tangent from 13, i.e. 13 − 9 ÷ 26: 12.6538 (0.04% high)

For √160 the tangent at 13 wins, missing by only 0.0047. Tangent estimates shine when the number sits close to a perfect square — here 160 is just 9 below 169.

1212² = 1441313² = 169√160 ≈ 12.6491
√160 on a number line, with tenths marked between 12 and 13.

Finding √160 with the Babylonian method

Picture a rectangle with an area of 160 and one side x; the other side must be 160 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √160.

xnext = (x + 160 ÷ x) ÷ 2

Start from the nearest whole number, 13 (13² = 169):

StepGuess x160 ÷ xAverageCorrect decimals
113.000000000012.307692307712.65384615382
212.653846153812.644376899712.64911152686
312.649111526812.649109754612.6491106407all 10 shown

The count of correct decimals went 2, 6 and all 10 over 3 steps — roughly doubling each time — until the guess matched √160 = 12.6491106407 to every decimal shown.

√160 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √160 the pattern is [12; 1, 1, 1, 5, 1, 1, 1, 24] with the block of 8 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √160 is irrational.

Cutting the continued fraction off early gives the best fractions for approximating the root — no fraction with a smaller denominator comes closer:

FractionDecimalError
12/112.00000000006.5 × 10⁻¹
13/113.00000000003.5 × 10⁻¹
25/212.50000000001.5 × 10⁻¹
38/312.66666666671.8 × 10⁻²
215/1712.64705882352.1 × 10⁻³
253/2012.65000000008.9 × 10⁻⁴

The same fractions solve Pell’s equation, x² − 160y² = 1. Its smallest solution in positive whole numbers is x = 721, y = 57.

√160 in geometry and everyday measurements

  • A square room or garden bed covering 160 square feet measures about 12.65 ft (12 ft 8 in) along each wall.
  • 160 = 4² + 12², so by the Pythagorean theorem √160 is the diagonal of a 4 × 12 rectangle — and the distance between the points (0, 0) and (4, 12) on a grid.
  • Since √160 = 4√10, a length of √160 is exactly 4 copies of the length √10 laid end to end.
RootSimplest formDecimalPerfect square?
√157√15712.5300No
√158√15812.5698No
√159√15912.6095No
√1604√1012.6491No
√161√16112.6886No
√1629√212.7279No
√163√16312.7671No
  • The cube root of 160 is about 5.428835.
  • Four times the radicand doubles the root: √640 = 2 × √160 ≈ 25.298221.

Frequently asked questions

What is the square root of 160?

The square root of 160 is 4√10 in simplest radical form, which is about 12.6491106407. The negative root, −12.649111, also squares to 160.

Is the square root of 160 rational or irrational?

Irrational. 160 is not a perfect square — it falls between 144 and 169 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √160 be simplified?

Yes. The largest perfect square dividing 160 is 16, so √160 = √16 × √10 = 4√10.

What is √160 rounded to two decimal places?

√160 ≈ 12.65 to two decimal places (12.6 to one, 12.649 to three). Check: 12.65² = 160.0225, close to 160.

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