Black horses will be black all over including the sides of the muzzle and on the flanks – they could be described as having black bodies & black points. Most horses that look Black are actually a very dark bay. Horses that are truly Black will look blueish-black compared to the brownish-black of Dark Bays. Black horses without any brown or red hairs can be quite hard to find.

Black occurs in most breeds and is considered the only colour in some breeds, such as the Friesian, although very rarely, chestnut freisians do occur. Some breeds have been specifically bred out the Black colour, for example the Suffolk Punch and Haflinger.

Non-Fading Black is just as it sounds, a Black horse that does not become "sunburned" or fade from effects of sun and weather nor sweat and saddles rubbing. Foals of this colour may be born a smokey or blue-black shade. These horses will only very rarely fade in extreme conditions.

Fading Black is a horse that fades from sun and weather. These foals are usually born a smokey ashen color, but may also be born a dark bay or brown. Mature horses usually fade to varying degrees and maintaining the rich, deep Black colour requires a lot of work. Regardless of whether they will fade or not when mature, your average Black foal will be a black colour with lighter sooty areas along the underside of it's body. It's normal for a Black foal to have light coloured legs.

Black pigment in mammals is called by Eumelanin. Black is one of the base colours for horses, the other is red (Chestnut). All horses will have a black or red base colour. Black horses are not capable of producing Bay foals unless the mate is a Bay or a Chestnut masking Agouti (see below).

The gene which produces black hair is symbolized by the letter ‘E’. Agouti, which controls the distribution of black hairs is symbolized by the letter ‘A’. Both black and bay horses will have at least one copy of the 'E' gene. If there is not a copy of the 'A' gene present, black hairs are distributed evenly all over the body, creating a Black horse. EE means the horse is genetically (homozygous) and physically Black, Ee means the horse is genetically (heterozygous) and physically Black, ee means the horse is genetically and physically Chestnut – this is assuming that there are no dilution or modifiying genes present.

A black horse put to a Black or Chestnut horse may produce a Black or a Chestnut foal to either pairing. A Black horse put to a Bay may produce a Black, Bay or Chestnut foal.

Black based colors include:
• Black diluted by Dun is called Grullo or Grulla or Black Dun or Blue Dun or Grey Dun
• Black diluted by Cream is either Smokey Black if one copy of Cream gene or Smokey Cream if two copies of Cream gene – this is the only modified version of Black that has a different appearance in single or double doses
• Black diluted by Silver is called Silver Dapple or Black Silver or Chocolate Silver
• Black diluted by Champagne is called Classic Champagne
• Black altered by Roan is called Black Roan or Blue Roan