Square Root of 1000

The square root of 1000 is 10√10 in simplest radical form, or about 31.6227766017 as a decimal.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
10√10
Decimal
31.6227766017
Both real square roots
±31.6227766017x² = 1,000 has two real solutions
Between
31² = 961 and 32² = 1,024so the root is between 31 and 32
Perfect power?
No
√1,00031.6227766017= 10√10

Show the work

  1. Prime-factor the radicand: 1,000 = 23 × 53 = (22 × 52) × 2 × 5.
  2. Each pair of identical factors comes out of the radical as a single factor: √1,000 = 10√10.
  3. Decimal value: √1,000 ≈ 31.6227766017.
  4. Check: 31.62277660172 ≈ 1,000.

√1000 at a glance

Exact value
10√10
Decimal (10 places)
31.6227766017
Rounded
31.6 · 31.62 · 31.623
Perfect square?
No — between 31² and 32²
Rational?
Irrational
Both square roots
±31.622777
Prime factorization
2³ × 5³
Cube root
10

How to simplify √1000

Look for the largest perfect square that divides 1000. Here it is 100 (10²), because 1000 = 100 × 10 and 10 has no square factor left:

√1000 = √(100 × 10) = √100 × √10 = 10√10

The prime factorization tells the same story: 1000 = 2³ × 5³. Each pair of equal primes leaves the radical as one factor, so 2 × 5 comes out and 2 × 5 stays inside.

1000 has 3 square factors (4, 25 and 100). Starting with a smaller one still works but takes more rounds: √1000 = 2√250, and √250 can be simplified again. Using 100 straight away finishes in one step.

Check: (10√10)² = 10² × 10 = 100 × 10 = 1000. As a decimal, 10√10 = 10 × 3.1622776602 ≈ 31.6227766017.

Where √1000 sits between perfect squares

961 = 31² and 1,024 = 32² are the nearest perfect squares, so √1000 lies between 31 and 32. 1000 is 39 above 961 and 24 below 1,024, so the root is closer to 32.

√1000 ≈ 31 + (1000 − 961) ÷ (1024 − 961) = 31 + 39/63 ≈ 31.6190
  • Straight line between 961 and 1,024: 31.6190 (0.01% low)
  • Tangent from 31, i.e. 31 + 39 ÷ 62: 31.6290 (0.02% high)
  • Tangent from 32, i.e. 32 − 24 ÷ 64: 31.6250 (0.01% high)

For √1000 the tangent at 32 wins, missing by only 0.0022. Tangent estimates shine when the number sits close to a perfect square — here 1000 is just 24 below 1,024.

3131² = 9613232² = 1,024√1000 ≈ 31.6228
√1000 on a number line, with tenths marked between 31 and 32.

Finding √1000 with the Babylonian method

Picture a rectangle with an area of 1000 and one side x; the other side must be 1000 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √1000.

xnext = (x + 1000 ÷ x) ÷ 2

Start from the nearest whole number, 32 (32² = 1,024):

StepGuess x1000 ÷ xAverageCorrect decimals
132.000000000031.250000000031.62500000002
231.625000000031.620553359731.62277667987
331.622776679831.622776523531.6227766017all 10 shown

The count of correct decimals went 2, 7 and all 10 over 3 steps — roughly doubling each time — until the guess matched √1000 = 31.6227766017 to every decimal shown.

√1000 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √1000 the pattern is [31; 1, 1, 1, 1, 1, 6, 2, 2, 15, 2, 2, 6, …] with the block of 18 terms after the semicolon repeating forever (only the first 12 of the 18 are shown). A pattern that never ends is one more proof that √1000 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
31/131.00000000006.2 × 10⁻¹
32/132.00000000003.8 × 10⁻¹
63/231.50000000001.2 × 10⁻¹
95/331.66666666674.4 × 10⁻²
158/531.60000000002.3 × 10⁻²
253/831.62500000002.2 × 10⁻³

The same fractions solve Pell’s equation, x² − 1000y² = 1. Its smallest solution in positive whole numbers is x = 39,480,499, y = 1,248,483.

√1000 in geometry and everyday measurements

  • 1,000 square feet is 92.9 m². Laid out as a square — a small house footprint or a lot — it is about 31.62 ft (31 ft 7 in) on a side.
  • 1000 = 10² + 30² = 18² + 26², so by the Pythagorean theorem √1000 is the diagonal of rectangles measuring 10 × 30 and 18 × 26 — and the distance between the points (0, 0) and (10, 30) on a grid.
  • Since √1000 = 10√10, a length of √1000 is exactly 10 copies of the length √10 laid end to end.

1,000 is 10³, so √1,000 = 10 to the power 1.5, or 10√10 ≈ 31.6228 — the point one and a half decades up a logarithmic scale.

RootSimplest formDecimalPerfect square?
√994√99431.5278No
√995√99531.5436No
√9962√24931.5595No
√997√99731.5753No
√998√99831.5911No
√9993√11131.6070No
√100010√1031.6228No
  • The cube root of 1000 is exactly 10 — 1000 is a perfect cube as well (10³).
  • Dividing by 100 divides the root by 10: √10 = √1000 ÷ 10 ≈ 3.16227766.

Frequently asked questions

What is the square root of 1000?

The square root of 1000 is 10√10 in simplest radical form, which is about 31.6227766017. The negative root, −31.622777, also squares to 1000.

Is the square root of 1000 rational or irrational?

Irrational. 1000 is not a perfect square — it falls between 961 and 1024 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √1000 be simplified?

Yes. The largest perfect square dividing 1000 is 100, so √1000 = √100 × √10 = 10√10.

What is √1000 rounded to two decimal places?

√1000 ≈ 31.62 to two decimal places (31.6 to one, 31.623 to three). Check: 31.62² = 999.8244, close to 1000.

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