Square Root of 223

The square root of 223 is about 14.9331845231. It is irrational and already in simplest form, written √223.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
√223
Decimal
14.9331845231
Both real square roots
±14.9331845231x² = 223 has two real solutions
Between
14² = 196 and 15² = 225so the root is between 14 and 15
Perfect power?
No
√22314.9331845231= √223

Show the work

  1. Prime-factor the radicand: 223 = 223.
  2. No prime appears 2 or more times, so √223 is already in simplest form.
  3. Decimal value: √223 ≈ 14.9331845231.
  4. Check: 14.93318452312 ≈ 223.

√223 at a glance

Exact value
√223
Decimal (10 places)
14.9331845231
Rounded
14.9 · 14.93 · 14.933
Perfect square?
No — between 14² and 15²
Rational?
Irrational
Both square roots
±14.933185
Prime factorization
223
Cube root
6.064127

How to simplify √223

223 is a prime number, so its only factors are 1 and 223. There is no perfect-square factor to pull out, which means √223 is already in its simplest radical form.

The square root of any prime is irrational. If √223 were a fraction a/b in lowest terms, then a² = 223b², so 223 would divide a — and then 223 would divide b too, contradicting “lowest terms.” That is why the decimal 14.9331845231 is only a rounded value.

Where √223 sits between perfect squares

196 = 14² and 225 = 15² are the nearest perfect squares, so √223 lies between 14 and 15. 223 is 27 above 196 and 2 below 225, so the root is closer to 15.

√223 ≈ 14 + (223 − 196) ÷ (225 − 196) = 14 + 27/29 ≈ 14.9310
  • Straight line between 196 and 225: 14.9310 (0.01% low)
  • Tangent from 14, i.e. 14 + 27 ÷ 28: 14.9643 (0.21% high)
  • Tangent from 15, i.e. 15 − 2 ÷ 30: 14.9333 (0% high)

For √223 the tangent at 15 wins, missing by only 0.0001. Tangent estimates shine when the number sits close to a perfect square — here 223 is just 2 below 225.

1414² = 1961515² = 225√223 ≈ 14.9332
√223 on a number line, with tenths marked between 14 and 15.

Finding √223 with the Babylonian method

If a guess is too big, 223 ÷ 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√223) in one step.

xnext = (x + 223 ÷ x) ÷ 2

Start from the nearest whole number, 15 (15² = 225):

StepGuess x223 ÷ xAverageCorrect decimals
115.000000000014.866666666714.93333333333
214.933333333314.933035714314.93318452389
314.933184523814.933184522314.9331845231all 10 shown

The count of correct decimals went 3, 9 and all 10 over 3 steps — roughly doubling each time — until the guess matched √223 = 14.9331845231 to every decimal shown.

√223 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √223 the pattern is [14; 1, 13, 1, 28] with the block of 4 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √223 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
14/114.00000000009.3 × 10⁻¹
15/115.00000000006.7 × 10⁻²
209/1414.92857142864.6 × 10⁻³
224/1514.93333333331.5 × 10⁻⁴
6,481/43414.93317972354.8 × 10⁻⁶
6,705/44914.93318485523.3 × 10⁻⁷

The same fractions solve Pell’s equation, x² − 223y² = 1. Its smallest solution in positive whole numbers is x = 224, y = 15.

√223 in geometry and everyday measurements

  • A square patio or deck of 223 square feet is about 14.93 ft (14 ft 11 in) on each side, so edging all the way around takes 4 × √223 ≈ 59.7 ft.
  • 223 is not a sum of two whole-number squares — 223 is itself a prime that is one less than a multiple of 4, which rules that out — so √223 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 √223 as its space diagonal.
RootSimplest formDecimalPerfect square?
√2202√5514.8324No
√221√22114.8661No
√222√22214.8997No
√223√22314.9332No
√2244√1414.9666No
√2251515.0000Yes
√226√22615.0333No
  • The cube root of 223 is about 6.064127.
  • Four times the radicand doubles the root: √892 = 2 × √223 ≈ 29.866369.

Frequently asked questions

What is the square root of 223?

The square root of 223 is √223, about 14.9331845231. The negative root, −14.933185, also squares to 223.

Is the square root of 223 rational or irrational?

Irrational. 223 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 √223 be simplified?

No. 223 is prime, so there is no perfect square to take out of the radical.

What is √223 rounded to two decimal places?

√223 ≈ 14.93 to two decimal places (14.9 to one, 14.933 to three). Check: 14.93² = 222.9049, close to 223.

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