Square Root of 199

The square root of 199 is about 14.1067359797. It is irrational and already in simplest form, written √199.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
√199
Decimal
14.1067359797
Both real square roots
±14.1067359797x² = 199 has two real solutions
Between
14² = 196 and 15² = 225so the root is between 14 and 15
Perfect power?
No
√19914.1067359797= √199

Show the work

  1. Prime-factor the radicand: 199 = 199.
  2. No prime appears 2 or more times, so √199 is already in simplest form.
  3. Decimal value: √199 ≈ 14.1067359797.
  4. Check: 14.10673597972 ≈ 199.

√199 at a glance

Exact value
√199
Decimal (10 places)
14.1067359797
Rounded
14.1 · 14.11 · 14.107
Perfect square?
No — between 14² and 15²
Rational?
Irrational
Both square roots
±14.106736
Prime factorization
199
Cube root
5.838272

How to simplify √199

199 is a prime number, so its only factors are 1 and 199. There is no perfect-square factor to pull out, which means √199 is already in its simplest radical form.

The square root of any prime is irrational. If √199 were a fraction a/b in lowest terms, then a² = 199b², so 199 would divide a — and then 199 would divide b too, contradicting “lowest terms.” That is why the decimal 14.1067359797 is only a rounded value.

Where √199 sits between perfect squares

196 = 14² and 225 = 15² are the nearest perfect squares, so √199 lies between 14 and 15. 199 is 3 above 196 and 26 below 225, so the root is closer to 14.

√199 ≈ 14 + (199 − 196) ÷ (225 − 196) = 14 + 3/29 ≈ 14.1034
  • Straight line between 196 and 225: 14.1034 (0.02% low)
  • Tangent from 14, i.e. 14 + 3 ÷ 28: 14.1071 (0% high)
  • Tangent from 15, i.e. 15 − 26 ÷ 30: 14.1333 (0.19% high)

For √199 the tangent at 14 wins, missing by only 0.0004. Tangent estimates shine when the number sits close to a perfect square — here 199 is just 3 above 196.

1414² = 1961515² = 225√199 ≈ 14.1067
√199 on a number line, with tenths marked between 14 and 15.

Finding √199 with the Babylonian method

If a guess is too big, 199 ÷ 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√199) in one step.

xnext = (x + 199 ÷ x) ÷ 2

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

StepGuess x199 ÷ xAverageCorrect decimals
114.000000000014.214285714314.10714285713
214.107142857114.106329113914.10673598558
314.106735985514.106735973814.1067359797all 10 shown

The count of correct decimals went 3, 8 and all 10 over 3 steps — roughly doubling each time — until the guess matched √199 = 14.1067359797 to every decimal shown.

√199 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √199 the pattern is [14; 9, 2, 1, 2, 2, 5, 4, 1, 1, 13, 1, 1, …] with the block of 20 terms after the semicolon repeating forever (only the first 12 of the 20 are shown). A pattern that never ends is one more proof that √199 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
14/114.00000000001.1 × 10⁻¹
127/914.11111111114.4 × 10⁻³
268/1914.10526315791.5 × 10⁻³
395/2814.10714285714.1 × 10⁻⁴
1,058/7514.10666666676.9 × 10⁻⁵
2,511/17814.10674157305.6 × 10⁻⁶

The same fractions solve Pell’s equation, x² − 199y² = 1. Its smallest solution in positive whole numbers is x = 16,266,196,520, y = 1,153,080,099.

√199 in geometry and everyday measurements

  • A square room or garden bed covering 199 square feet measures about 14.11 ft (14 ft 1 in) along each wall.
  • 199 is not a sum of two whole-number squares — 199 is itself a prime that is one less than a multiple of 4, which rules that out — so √199 is never the diagonal of a rectangle with whole-number sides. It is not a sum of three positive squares either, so no whole-number box has √199 as its space diagonal.
RootSimplest formDecimalPerfect square?
√1961414.0000Yes
√197√19714.0357No
√1983√2214.0712No
√199√19914.1067No
√20010√214.1421No
√201√20114.1774No
√202√20214.2127No
  • The cube root of 199 is about 5.838272.
  • Four times the radicand doubles the root: √796 = 2 × √199 ≈ 28.213472.

Frequently asked questions

What is the square root of 199?

The square root of 199 is √199, about 14.1067359797. The negative root, −14.106736, also squares to 199.

Is the square root of 199 rational or irrational?

Irrational. 199 is not a perfect square — it falls between 196 and 225 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √199 be simplified?

No. 199 is prime, so there is no perfect square to take out of the radical.

What is √199 rounded to two decimal places?

√199 ≈ 14.11 to two decimal places (14.1 to one, 14.107 to three). Check: 14.11² = 199.0921, close to 199.

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