18 millimeters to centimeters
1.80 cm
18 mm = 1.80 cm.
centimeters
1.80cm
18 mm = 1.80 cm
In short
How many centimeters is 18 millimeters?
18 mm = 1.80 cm. 1 millimeter = 0.100000 centimeters, so the working is 18 × 0.100000 = 1.80.
The working
The factor below is an exact definition rather than a measurement, so nothing is approximated in the arithmetic. The only rounding on this page happens where a number is displayed.
1 millimeter = 0.100000 centimeters 18 × 0.100000 = 1.80
How much precision do you need?
Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.
| Rounded to | Answer (cm) | Off by |
|---|---|---|
| Whole number | 2 | +0.20000 |
| 1 decimal | 1.8 | exact |
| 2 decimals | 1.80 | exact |
Round trip: take 1.80 cm back the other way and you land on 18.0000 mm — a drift of 0.0000 mm. That gap is the rounding, not the conversion.
Frequently asked questions
What is 18 millimeters in centimeters?
18 millimeters is 1.80 centimeters. 1 millimeter = 0.100000 centimeters, so the working is 18 × 0.100000 = 1.80.
How accurate is 1.80 cm?
Rounding to 1.80 cm and converting straight back gives 18.0000 mm, a drift of 0.0000 mm from the 18 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.
Nearby values
Any value at all
Millimeters to Centimeters Converter
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