3/13

Fraction3/13
Decimal≈ 0.2307692308exactly 0.(230769)
Percent≈ 23.076923%exactly 23.(076923)%

3 of 13 equal parts filled — the same share as a bar and as a circle.

Where the decimal comes from

There is no rewrite over 10, 100 or 1000 for 3/13: 13 has a prime factor other than 2 and 5, so no whole-number multiplier reaches a power of ten. Watch the long division to see what happens instead — the remainders start circling, and once a remainder comes back, the digits must too:

  1. 30 ÷ 13 = 2remainder 4
  2. 40 ÷ 13 = 3remainder 1
  3. 10 ÷ 13 = 0remainder 10
  4. 100 ÷ 13 = 7remainder 9
  5. 90 ÷ 13 = 6remainder 12
  6. 120 ÷ 13 = 9remainder 3— this remainder has come around before, so from here the digits repeat

Written exactly: 0.(230769) — the parentheses mark the block that repeats forever.

Every way to write it

Decimal
≈ 0.2307692308
Percent
≈ 23.076923%
Ratio
3 : 13 (part to whole)
As inches
3/13″ = 5.861538 mm

Equivalent fractions

Multiply the top and bottom of 3/13 by the same number and the value does not change:

3/13 = 6/26 = 9/39 = 12/52 = 15/65 = 18/78 · more, or pick a denominator

On the number line

0 1 3/13

As a measurement

Read as inches, 3/13″ is 5.861538 mm exactly. The nearest marks on the finer rules:

RuleNearest markDecimal inchesmmDifference
16ths1/4″ 0.256.35+0.4885 mm
32ths7/32″ 0.218755.5563−0.3053 mm
64ths15/64″ 0.2343755.9531+0.0916 mm

Need a different rule or a tolerance? Nearest fraction · Within tolerance

Common questions

What is 3/13 as a decimal?
3/13 is 0.2307692308 rounded; exactly, it is the repeating decimal 0.(230769).
What is 3/13 as a percentage?
3/13 is about 23.076923% as a percentage.
How many millimetres is 3/13 of an inch?
3/13 of an inch is 5.861538 mm, computed with the exact definition 1 inch = 25.4 mm.

Related

Fraction–decimal chartThe everyday set, printable.Rule charts16ths, 32nds, 64ths, 128ths.The rulerSee 3/13 in its place.
Where this comes from. Exact rational arithmetic on the values shown — fractions are pairs of integers until display, and inch–metric conversion uses 25.4 mm to the inch, exact by definition since 1959. See the full methodology.