Square Root of 195

The square root of 195 is about 13.9642400438. It is irrational and already in simplest form, written √195.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
√195
Decimal
13.9642400438
Both real square roots
±13.9642400438x² = 195 has two real solutions
Between
13² = 169 and 14² = 196so the root is between 13 and 14
Perfect power?
No
√19513.9642400438= √195

Show the work

  1. Prime-factor the radicand: 195 = 3 × 5 × 13.
  2. No prime appears 2 or more times, so √195 is already in simplest form.
  3. Decimal value: √195 ≈ 13.9642400438.
  4. Check: 13.96424004382 ≈ 195.

√195 at a glance

Exact value
√195
Decimal (10 places)
13.9642400438
Rounded
14.0 · 13.96 · 13.964
Perfect square?
No — between 13² and 14²
Rational?
Irrational
Both square roots
±13.964240
Prime factorization
3 × 5 × 13
Cube root
5.798890

How to simplify √195

The prime factorization of 195 is 3 × 5 × 13. Every prime appears only once, so there is no pair to bring outside the radical — √195 is already in simplest form (a "square-free" radicand).

A whole number has a rational square root only when every prime in its factorization appears an even number of times. In 195, 3, 5 and 13 appear an odd number of times, so √195 is irrational and 13.9642400438 is a rounded value.

Where √195 sits between perfect squares

169 = 13² and 196 = 14² are the nearest perfect squares, so √195 lies between 13 and 14. 195 is 26 above 169 and 1 below 196, so the root is closer to 14.

√195 ≈ 13 + (195 − 169) ÷ (196 − 169) = 13 + 26/27 ≈ 13.9630
  • Straight line between 169 and 196: 13.9630 (0.01% low)
  • Tangent from 13, i.e. 13 + 26 ÷ 26: 14.0000 (0.26% high)
  • Tangent from 14, i.e. 14 − 1 ÷ 28: 13.9643 (0% high)

For √195 the tangent at 14 wins, missing by only 0. Tangent estimates shine when the number sits close to a perfect square — here 195 is just 1 below 196.

1313² = 1691414² = 196√195 ≈ 13.9642
√195 on a number line, with tenths marked between 13 and 14.

Finding √195 with the Babylonian method

If a guess is too big, 195 ÷ x is too small by about the same amount, so their average lands much closer. In fact an error of e shrinks to roughly e² ÷ (2√195) in one step.

xnext = (x + 195 ÷ x) ÷ 2

Start from the nearest whole number, 14 (14² = 196):

StepGuess x195 ÷ xAverageCorrect decimals
114.000000000013.928571428613.96428571434
213.964285714313.964194373413.964240043810
313.964240043813.964240043713.9642400438all 10 shown

The count of correct decimals went 4, 10 and all 10 over 3 steps — roughly doubling each time — until the guess matched √195 = 13.9642400438 to every decimal shown.

√195 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √195 the pattern is [13; 1, 26] with the block of 2 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √195 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
13/113.00000000009.6 × 10⁻¹
14/114.00000000003.6 × 10⁻²
377/2713.96296296301.3 × 10⁻³
391/2813.96428571434.6 × 10⁻⁵
10,543/75513.96423841061.6 × 10⁻⁶
10,934/78313.96424010225.8 × 10⁻⁸

The same fractions solve Pell’s equation, x² − 195y² = 1. Its smallest solution in positive whole numbers is x = 14, y = 1.

√195 in geometry and everyday measurements

  • A square room or garden bed covering 195 square feet measures about 13.96 ft (14 ft) along each wall.
  • 195 is not a sum of two whole-number squares — the prime factor 3 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √195 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 1 × 5 × 13 box, because 1² + 5² + 13² = 195.
RootSimplest formDecimalPerfect square?
√1928√313.8564No
√193√19313.8924No
√194√19413.9284No
√195√19513.9642No
√1961414.0000Yes
√197√19714.0357No
√1983√2214.0712No
  • The cube root of 195 is about 5.798890.
  • Four times the radicand doubles the root: √780 = 2 × √195 ≈ 27.92848.

Frequently asked questions

What is the square root of 195?

The square root of 195 is √195, about 13.9642400438. The negative root, −13.964240, also squares to 195.

Is the square root of 195 rational or irrational?

Irrational. 195 is not a perfect square — it falls between 169 and 196 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √195 be simplified?

No. 195 = 3 × 5 × 13 has no repeated prime factor, so there is no perfect square to take out of the radical.

What is √195 rounded to two decimal places?

√195 ≈ 13.96 to two decimal places (14.0 to one, 13.964 to three). Check: 13.96² = 194.8816, close to 195.

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