This question is a bit tricky! "One" doesn't have a standard unit of measurement. To answer how many centimetres are in "one", we need to know what "one" refers to.

For example, if you meant:

* One metre: There are 100 centimetres in one metre.

* One inch: There are 2.54 centimetres in one inch.

* One foot: There are 30.48 centimetres in one foot.

Please clarify what you mean by "one" so I can give you the correct answer!