hains come in either 11/128", 3/32", 1/8", 5/32", or 3/16" roller widths, the internal width between the inner plates. 1/8" chains are used on bikes with a single rear sprocket: those with , ,  such as , or  bikes. Chains with 3/32" wide rollers are used on bikes with  such as , , and . Fixed sprockets and freewheels are also available in 3/32" widths so fixed-gear and  bikes can be set up to use narrow and lighter 3/32" chains. Finally, chains with 5/32" wide rollers are used on  and .

With derailleur equipped bicycles, the external width of the chain also matters, because chains must not be too wide for the  or they will rub on the next larger sprocket or too narrow that they might fall between two sprockets. Chains can also be identified by the number of rear sprockets they can support, anywhere from 3 to 11, and the list below enables measuring a chain of unknown origin to determine its suitability.