Коронет: Символ дворянского достоинства в геральдике.

Small crown consisting of ornaments fixed on a metal ring

In British heraldry, a coronet is any crown whose bearer is less than sovereign or royal in rank, irrespective of the crown's appearance. In other languages, this distinction is not made, and usually the same word for crown is used irrespective of rank (Krone, Kroon, Krona, , , etc.) In this use, the English coronet is a purely technical term for all heraldic images of crowns not used by a sovereign, and implies nothing about the actual shape of the crown depicted. A Coronet is another type of crown, but is reserved for the lower ranks of nobility like Marquesses and Marchionesses, Earls and Countesses, Barons and Baronesses, and some Lords and Ladies. The specific design and attributes of the crown or coronet signifies the hierarchy and ranking of its owner. Certain physical coronets are worn by the British peerage on rare ceremonial occasions, such as the coronation of the monarch. These are also sometimes depicted in heraldry, and called coronets of rank in heraldic usage. Their shape varies depending on the wearer's rank in the peerage, according to models laid down in the 16th century. Similar depictions of crowns of rank (Rangkronen) are used in continental heraldry, but physical headgear has never been made to imitate them. Due to the extreme rarity of occasions in which peers' coronets are worn (sometimes more than fifty years pass before a new coronation and occasion to wear physical coronets), practical use of the term coronet today is almost exclusively confined to pictorial crowns and rank symbols in heraldry, adorning someone's coat of arms (indeed, many people entitled to a coronet never have a physical one made). Depiction of ordinary crowns or coronets in heraldry, rather than coronets of rank, including a variety of crest coronets sometimes placed under the crest, are not confined to peers, and are often shown in British heraldry outside the peerage.

The word stems from the Old French coronete, a diminutive of co(u)ronne ('crown'), itself from the corona and from the κορώνη. Traditionally, such headgear is used by nobles and by princes and princesses in their coats of arms, rather than by monarchs, for whom the word 'crown' is customarily reserved in English, while many languages have no such terminological distinction. As a coronet shows the rank of the respective noble, in the German and Scandinavian languages there is also the term rangkrone (literally 'rank crown').

Traditionally, in the United Kingdom, a peer wears the coronet on one occasion only: for a royal coronation, when it is worn along with coronation robes, equally standardised as a luxurious uniform. However, for the 2023 coronation of King Charles III, on the government's advice, the King forbade the wearing of coronets by those peers who have been invited, except those performing specific ceremonial roles. In the peerages of the United Kingdom, the design of a coronet shows the rank of its owner, as in German, French and various other heraldic traditions. Dukes were the first individuals authorised to wear coronets. Marquesses acquired coronets in the 15th century, earls in the 16th and viscounts and barons in the 17th. Until the barons received coronets in 1661, the coronets of earls, marquesses and dukes were engraved while those of viscounts were plain. After 1661, however, viscomital coronets became engraved, while baronial coronets were plain. Coronets may not bear any precious or semi precious stones. Since a person entitled to wear a coronet customarily displays it in their coat of arms above the shield and below the helmet and crest, this can provide a useful clue as to the owner of a given coat of arms. In Canadian heraldry, descendants of the United Empire Loyalists are entitled to use a Loyalist military coronet (for descendants of members of Loyalist regiments) or Loyalist civil coronet (for others) in their arms.

The Holy Roman Empire, and consequently its successor states (Austria, Germany and others), had a system very similar to that of the British, although the design varied. Herzogskrone: the coronet of a Herzog (duke) displays five visible leaves, with a crimson bonnet on top, surmounted by five visible arches and a globus cruciger. Fürstenkrone: the coronet of a Fürst (ruling prince) shows five visible leaves, with a crimson bonnet on top, surmounted by three visible arches and a globus cruciger. Landgrafenkrone: the coronet of a Landgraf (landgrave) shows five visible leaves, surmounted by three visible arches and a globus cruciger. Grafenkrone: the coronet of a Graf (count) displays nine visible tines with pearls. Some of the senior comital houses used coronets showing five leaves and four pearls (some mediatized counties and minor principalities had other types of coronets that distinguished them from regular counts). Freiherrnkrone: the coronet of a Freiherr (baron) shows seven visible tines with pearls. Adelskrone: the coronet of Adel members (untitled nobility) displays five visible tines with pearls. Sometimes, the central and outer tines are leaves and the other tines are headed by pearls. In the southern states of Bavaria and Württemberg, usually all tines are headed by pearls. Considering the religious nature of the Holy Roman Empire, one can say that, except for the short lived Napoleonic states, no continental secular system of heraldry historically was so neatly regulated as under the British crown. Still, there are often traditions (often connected to the Holy Roman Empire, e. g., those in Sweden, Denmark or Russia) that include the use of crown and coronets. While most languages do not have a specific term for coronets, but simply use the word meaning crown, it is possible to determine which of those crowns are for peerage or lower level use, and thus can by analogy be called coronets. Precisely because there are many traditions and more variation within some of these, there is a plethora of continental coronet types. Indeed, there are also some coronets for positions that do not exist or entitle one to a coronet in the Commonwealth tradition. Such a case in French (ancien, i. e., royal era) heraldry, where coronets of rank did not come into use before the 16th century, is the vidame, whose coronet (illustrated) is a metal circle mounted with three visible crosses (there is no documentary or archeological evidence that such a coronet was ever made). Often, coronets are substituted by helmets, or only worn on a helmet.

Although these crowns/coronets were usually granted with arms, sometimes the coronet was not granted.