This is a question I see often from pet owners when they get a puppy with a dark mask.  Often times it can be a little difficult to tell if a puppy is going to grow up to be sesame or red. Red puppies, not always, but often times have many grey and dark hairs before getting their adult coats in, especially around their muzzles. This is normal. Sometimes a dog will not loose its black mask even into adulthood, although they are supposed to. 

Pictured below, a puppy with a black mask and dark hairs but is still a red dog, as he aged his coat changed significantly.

Genes Responsible for Sesame: AysAys, AysAt, AysAw, AwAw, AwAt

The sure way to get your answer is VIA a genetic test, which most tests right now can identify the (AW) gene. As for the AY(s) gene, it is a newly discovered gene for sesame that can only be detected by UC DAVIS for the time being. 

Sesames can either have a strong widows peak, or the black hairs can even reach to the bridge of the nose and under the eyes. Dark ring hairs around the outside of the eye and dark ticking evenly distributed on the body is usually a good indication of a sesame. 

AKC Sesame Standard:

Sesame (black-tipped hairs on a rich red background) with urajiro. Tipping is light and even on the body and head with no concentration of black in any area. Sesame areas appear at least one-half red. Sesame may end in a widow’s peak on the forehead, leaving the bridge and sides of the muzzle red. Eye spots and lower legs are also red. Clearly delineated white markings are permitted but not required on the tip of the tail and in the form of socks on the forelegs to the elbow joint, hind legs to the knee joint. A patch of blaze is permitted on the throat, forechest, or chest in addition to urajiro.

AKC Breed Standard

Study Pictures Below

Other Coat Types Usually Mistaken for Sesame

Other coat colors that are usually mistaken by amateur breeders or pet owners but are not actually sesame: reds who kept their black masks, “sashige” also called a dirty red, and saddleback/creeping tan/red headed.

Not Sesame:

• A red with a black mask – a dark muzzle
• Sashige (dirty red) – Significant black ticking on back but not enough to be saddle back.
• Saddleback/Creeping Tan – a dark body and head head, sometimes they have what looks like “sideburns”