A birthday cake is a cake eaten as part of a birthday celebration. While there is no standard for birthday cakes, they are typically highly decorated layer cakes covered in frosting, often featuring birthday wishes (“Happy birthday”) and the celebrant’s name. In many cultures, it is also customary to serve the birthday cake with small lit candles on top, especially in the case of a child’s birthday. Variations include cupcakes, cake pops, pastries, and tarts. In more recent years, it has become a common flavour for confectionery including ice cream, PopTarts, various cereal varieties among others. The flavour is usually vanilla with sweeter hints to imply sprinkles.

Birthday cakes have been a part of birthday celebrations in Western European countries since the middle of the 19th century.^[1] However, the link between cakes and birthday celebrations may date back to ancient Roman times; in classical Roman culture, cakes were occasionally served at special birthdays and at weddings. These were flat circles made from flour and nuts, leavened with yeast, and sweetened with honey.^{[citation needed]}

In the 15th century, bakeries in Germany began to market one-layer cakes for customers’ birthdays in addition to cakes for weddings.^{[citation needed]} During the 17th century, the birthday cake took on its contemporary form. These elaborate cakes had many aspects of the contemporary birthday cake, like multiple layers, icing, and decorations. However, these cakes were only available to the very wealthy. Birthday cakes became accessible to the lower class as a result of the industrial revolution and the spread of more materials and goods.

The practice of serving cake on birthdays is commonplace in many cultures. In contemporary Western cultures, birthday cakes for children are often topped with small candles, secured with special holders or simply pressed down into the cake. In the Anglosphere, the number of candles often corresponds to the age of the individual being celebrated, occasionally with one extra for luck.^[2] An increasingly popular alternative is to use candles shaped as the numeral digits of the celebrant’s age. Sparklers may also be used alongside or instead of the traditional wax candles.

The cake is usually presented with all the candles lit, at which point it is customary for the guests to sing Happy Birthday to You in unison, or an equivalent birthday song appropriate to the country. Upon the conclusion of the song, the celebrant is traditionally prompted to blow out the candles and make a wish, which is thought to come true if all the candles are extinguished in a single breath. Another common superstition holds that the wish must be made in silence, not to be shared with anyone else.