Fraction1/18
Fraction1/18
Decimal≈ 0.0555555556exactly 0.0(5)
Percent≈ 5.555556%exactly 5.(5)%
Where the decimal comes from
There is no rewrite over 10, 100 or 1000 for 1/18: 18 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:
- 10 ÷ 18 = 0remainder 10
- 100 ÷ 18 = 5remainder 10— this remainder has come around before, so from here the digits repeat
Written exactly: 0.0(5) — the parentheses mark the block that repeats forever.
Every way to write it
- Decimal
- ≈ 0.0555555556
- Percent
- ≈ 5.555556%
- Ratio
- 1 : 18 (part to whole)
- As inches
- 1/18″ = 1.411111 mm
Equivalent fractions
Multiply the top and bottom of 1/18 by the same number and the value does not change:
1/18 = 2/36 = 3/54 = 4/72 = 5/90 = 6/108 · more, or pick a denominator
On the number line
As a measurement
Read as inches, 1/18″ is 1.411111 mm exactly. The nearest marks on the finer rules:
| Rule | Nearest mark | Decimal inches | mm | Difference |
|---|---|---|---|---|
| 16ths | 1/16″ | 0.0625 | 1.5875 | +0.1764 mm |
| 32ths | 1/16″ | 0.0625 | 1.5875 | +0.1764 mm |
| 64ths | 1/16″ | 0.0625 | 1.5875 | +0.1764 mm |
Need a different rule or a tolerance? Nearest fraction · Within tolerance
Common questions
- What is 1/18 as a decimal?
- 1/18 is 0.0555555556 rounded; exactly, it is the repeating decimal 0.0(5).
- What is 1/18 as a percentage?
- 1/18 is about 5.555556% as a percentage.
- How many millimetres is 1/18 of an inch?
- 1/18 of an inch is 1.411111 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 1/18 in its place.