A decanter is a vessel that is used to hold the decantation of a liquid (such as wine) which may contain sediment. Decanters, which have a varied shape and design, have been traditionally made from glass or crystal. Their volume is usually equivalent to one standard bottle of wine (0.75 litre).

A carafe, which is also traditionally used for serving alcoholic beverages, is similar in design to a decanter but is not supplied with a stopper.

Throughout the history of wine, decanters have played a significant role in the serving of wine. The vessels would be filled with wine from amphoras and brought to the table where they could be more easily handled by a single servant.

The Ancient Romans pioneered the use of glass as a material. After the fall of the Western Roman Empire, glass production became scarce, causing the majority of decanters to be made of bronze, silver, gold, or earthenware. The Venetians reintroduced glass decanters during the Renaissance period and pioneered the style of a long slender neck that opens to a wide body, increasing the exposed surface area of the wine, allowing it to react with air.

In the 1730s, British glass makers introduced the stopper to limit exposure to air. Since then, there has been little change to the basic design of the decanter.

Liquid from another vessel is poured into the decanter in order to separate a small volume of liquid, containing the sediment, from a larger volume of "clear" liquid, which is free of such. In the process, the sediment is left in the original vessel, and the clear liquid is transferred to the decanter. This is analogous to racking, but performed just before serving.

Decanters have been used for serving wines that are laden with sediments in the original bottle. These sediments could be the result of a very old wine or one that was not filtered or clarified during the winemaking process. In most modern winemaking, the need to decant for this purpose has been significantly reduced, because many wines no longer produce a significant amount of sediment as they age.

Baskets called decanting cradles, usually made of wicker or metal, are used to decant bottles that have been stored on their side without needing to turn them upright, thereby avoiding stirring up sediment. These are particularly useful in restaurants, for service of a wine ordered during a meal, but less important at home, where a bottle can be stood upright the day before. More complicated decanting machines also exist to facilitate smoothly pouring, without disturbing sediment.