There are numerous classifications and types of errors that are due to the incorrect striking of a coin. Examples include off-center strikes, numerous strikes, switched dies, uneven dies, ineffective strikes, and overstrikes.

There are five types of mint errors that predominantly relate to the die of the coin: die breaks, uneven dies, conflicted dies, alternated dies, and combined variations.

One of the most popular error coins is the off-center struck coin. When the space is fed into the press inappropriately, it strikes the coin improperly because the dies only strike the blank that is inserted in the press and throws everything off.

An error coin is a currency that was not appropriately created during its manufacture or is beyond of adequate tolerance thresholds. Error coins may have problems such as being struck off-middle, having the incorrect planchet type, the circle and base of the coin, having the planchets improperly manufactured so they are too thick, or too thin, improperly made, or any number of other complications that occur during coin manufacturing, like bending or swirls along the edges.

Additionally, the coin die may be smashed during manufacture and lead to various error denominations being produced from the damaged coin dies. For example, it may crack due to misuse. Equally, a coin die may not have been manufactured accurately will also lead to an assortment of coin errors.