Siling labuyo is a small chili pepper cultivar that developed in the Philippines after the Columbian Exchange. It belongs to the species Capsicum frutescens and is characterized by triangular fruits which grow pointing upwards. The fruits and leaves are used in traditional Filipino cuisine. The fruit is pungent, ranking at 80,000 to 100,000 heat units in the Scoville Scale.
The cultivar name is Tagalog, and literally translates to "wild chili." It is also known simply as labuyo or labuyo chili. It is also sometimes known as Filipino bird's eye, to differentiate it from the Thai bird's eye chili. Both are commonly confused with each other in the Philippines, though they are cultivars of two different species. Siling labuyo is one of two common kinds of local chili found in the Philippines, the other being siling haba (a Capsicum annuum cultivar).
Siling labuyo is generally accepted as the world's smallest hot pepper, as the fruit often measure a mere 0.20 in (0.51 cm) in length by 0.10 in (0.25 cm) in width
It is listed in the Ark of Taste international catalog of endangered heritage foods of the Philippines by the Slow Food movement.